Complete guide to subscribing, managing, and troubleshooting Stripe credit card payments for FortiBlox Nexus

Credit Card Payments with Stripe

FortiBlox Nexus uses Stripe for secure, reliable credit card processing. This guide covers everything you need to know about subscribing, managing your subscription, and handling payment issues.

Why Use Credit Card Payments?

Advantages:

Instant subscription activation
Automatic monthly billing
Easy to upgrade/downgrade
Self-service billing portal
Invoice history and PDF receipts
PCI-compliant security
Fraud protection
Familiar checkout experience

Accepted Cards:

Visa
Mastercard
American Express
Discover
Diners Club
JCB

If you haven't already:

Go to nexus.fortiblox.com/signup
Create your account (email, Google, GitHub, or Telegram)
Verify your email address
You'll start on the Free tier automatically

Step 2: Choose Your Tier

Log into Developer Portal
Navigate to Billing → Pricing
Review tier features and pricing
Click "Subscribe" on your chosen tier

Step 3: Enter Payment Details

You'll be redirected to Stripe Checkout (secure payment page):

Email: Pre-filled with your account email
Card Information:
- Card number
- Expiration date (MM/YY)
- CVC security code
- ZIP/Postal code
Name on card: Cardholder name
Billing address: Required for tax calculation

Screenshot Placeholder

[IMAGE: Stripe Checkout page showing payment form]
Location: /docs/images/billing/stripe-checkout.png

Step 4: Complete Payment

Review subscription details:
- Tier name
- Monthly price
- Tax (if applicable)
- Total amount
Click "Subscribe" button
Wait for payment processing (usually 1-3 seconds)
3D Secure authentication may be required for some cards

3D Secure Authentication

Some cards require additional verification:

You'll see a popup from your bank
Enter your 3D Secure password or code
Approve the payment
Return to FortiBlox

[IMAGE: 3D Secure authentication popup]
Location: /docs/images/billing/3ds-auth.png

Step 5: Confirmation

After successful payment:

You'll be redirected to Developer Portal
See confirmation: "Subscription activated!"
Your tier is updated immediately
Credits are reset to your new tier's allocation
Receive confirmation email with receipt

Managing Your Subscription

View Subscription Details

Access your subscription information:

Log into Developer Portal
Navigate to Billing → Subscription

You'll see:

Current tier
Monthly cost
Next billing date
Payment method (last 4 digits)
Credits used this period
Credits remaining

// Or fetch via API
const response = await fetch('https://nexus.fortiblox.com/api/subscription', {
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY'
  }
});

const subscription = await response.json();
console.log(subscription);
/*
{
  subscription_id: 'sub_1QKmN4B5tZ...',
  tier: 'developer',
  status: 'active',
  current_period_start: '2025-11-21T00:00:00Z',
  current_period_end: '2025-12-21T00:00:00Z',
  cancel_at_period_end: false,
  credits_allocated: 50000000,
  credits_used: 12500000,
  credits_remaining: 37500000
}
*/

Update Payment Method

Change your credit card without interrupting service:

Via Developer Portal

Navigate to Billing → Subscription
Click "Update Payment Method"
You'll be redirected to Stripe Customer Portal
Click "Update payment method"
Enter new card details
Click "Save"
Return to Developer Portal

Via Stripe Customer Portal

Direct link: Manage Billing

Enter your email address
Check email for verification code
Enter code to access portal
Click "Update payment method"
Enter new card details
Save changes

// Or get Customer Portal link via API
const response = await fetch('https://nexus.fortiblox.com/api/billing/portal', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    return_url: 'https://nexus.fortiblox.com/billing'
  })
});

const { url } = await response.json();
// Redirect user to this URL
window.location.href = url;

Upgrade Your Tier

Upgrade to a higher tier at any time:

Navigate to Billing → Pricing
Click "Upgrade" on desired tier
Review prorated charge:
- Remaining time on current tier is credited
- New tier price is charged
- You pay the difference
Click "Confirm Upgrade"
Payment processed immediately
Credits updated to new tier
Rate limits increased immediately

Prorated Charge Example

Current Tier: Developer ($49/month)
New Tier: Business ($499/month)
Days into billing cycle: 15 of 30
Days remaining: 15

Calculation:
- Credit for unused Developer time: $49 × (15/30) = $24.50
- Charge for remaining Business time: $499 × (15/30) = $249.50
- Net charge: $249.50 - $24.50 = $225.00

You pay: $225.00
Next billing: Full $499.00 in 15 days

// Upgrade via API
const response = await fetch('https://nexus.fortiblox.com/api/billing/upgrade', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    new_tier: 'business'
  })
});

const result = await response.json();
console.log(result);
/*
{
  success: true,
  message: 'Successfully upgraded to business tier',
  subscription: {
    id: 'sub_1QKmN4B5tZ...',
    tier: 'business',
    proration_amount: 22500, // cents
    next_billing_amount: 49900, // cents
    next_billing_date: '2025-12-06T00:00:00Z'
  }
}
*/

Downgrade Your Tier

Downgrade to a lower tier (takes effect at period end):

Navigate to Billing → Pricing
Click "Downgrade" on desired tier
Review downgrade terms:
- Change takes effect at end of current billing period
- No refund for current period
- Continue using current tier until then
- Credits will decrease at period end
Click "Confirm Downgrade"
Confirmation message displayed
Email confirmation sent

Important: Downgrade is scheduled but not immediate. You keep full access to your current tier until the billing period ends.

// Downgrade via API
const response = await fetch('https://nexus.fortiblox.com/api/billing/downgrade', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    new_tier: 'developer'
  })
});

const result = await response.json();
console.log(result);
/*
{
  success: true,
  message: 'Downgrade scheduled for end of billing period',
  subscription: {
    id: 'sub_1QKmN4B5tZ...',
    current_tier: 'business',
    scheduled_tier: 'developer',
    effective_date: '2025-12-21T00:00:00Z'
  }
}
*/

Cancel Subscription

You can cancel your subscription at any time:

See complete cancellation guide →

Invoice History

View Past Invoices

Access all your invoices:

Navigate to Billing → Invoices
See list of all past invoices
Click invoice to view details

Each invoice shows:

Invoice number
Date
Amount charged
Payment method used
Tax amount (if applicable)
PDF download link

Via Stripe Customer Portal

Access Customer Portal
Navigate to "Invoice history" tab
View all invoices
Download PDF receipts

// Get invoice history via API
const response = await fetch('https://nexus.fortiblox.com/api/billing/invoices', {
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY'
  }
});

const invoices = await response.json();
console.log(invoices);
/*
{
  invoices: [
    {
      id: 'in_1QKmN4B5tZ...',
      number: 'FB-2025-001',
      amount_paid: 4900, // cents
      currency: 'usd',
      status: 'paid',
      created: 1732147200,
      period_start: '2025-11-21T00:00:00Z',
      period_end: '2025-12-21T00:00:00Z',
      invoice_pdf: 'https://pay.stripe.com/invoice/.../pdf',
      hosted_invoice_url: 'https://pay.stripe.com/invoice/...'
    },
    // ... more invoices
  ]
}
*/

Download PDF Receipts

Find invoice in Billing → Invoices
Click "Download PDF" button
PDF receipt opens in new tab
Save or print as needed

PDF includes:

Your business details
FortiBlox business details
Invoice date and number
Subscription details
Amount breakdown
Payment method
Tax information

Email Receipts

After each successful payment, you'll receive:

Subject: "Receipt from FortiBlox [#FB-2025-001]"
From: FortiBlox (via Stripe)
Contents:
- Payment confirmation
- Amount charged
- PDF receipt attachment
- Link to view online

Payment Issues

Failed Payment Handling

If a payment fails:

Immediate notification: Email sent immediately
Automatic retry: Stripe retries payment in 3 days
Second retry: 5 days after first retry
Third retry: 7 days after second retry
Final notification: If all retries fail

Total retry period: Up to 15 days

During retry period:

✅ Full access to your tier
✅ Credits available
⚠️ "Past Due" status shown
📧 Email reminders sent

If all retries fail:

❌ Subscription cancelled
❌ Downgrade to Free tier
📧 Final notice email sent

Common Failure Reasons

Reason	Solution
Insufficient funds	Add funds to bank account, update payment method
Expired card	Update payment method with new expiration date
Card declined by bank	Contact your bank, try different card
Incorrect CVC	Update payment method with correct CVC
Address mismatch	Update billing address
3D Secure failed	Complete 3D Secure authentication
Card not supported	Use Visa, Mastercard, Amex, or Discover

How to Resolve Failed Payment

Option 1: Update Payment Method

Navigate to Billing → Subscription
Click "Update Payment Method"
Enter new card details
Payment will be retried immediately

Option 2: Retry Payment

Navigate to Billing → Subscription
If payment failed, you'll see "Retry Payment" button
Click to process payment again with existing card
May be prompted for 3D Secure

Option 3: Contact Support

If you continue having issues:

Email: [email protected]

Include:

Your account email
Last 4 digits of card
Error message (if any)
Screenshot of issue

Response time: Within 24 hours

Grace Period

During the retry period (up to 15 days):

✅ You can:

Continue using your paid tier
Access all credits
Use all features
Update payment method
Upgrade tier (to retry with higher amount)

❌ You cannot:

Downgrade tier (would prevent payment recovery)
Cancel subscription (must resolve payment first)

Preventing Payment Failures

Set up backup payment method:

Access Stripe Customer Portal
Add second payment method
Stripe will try backup if primary fails

Enable email notifications:

Verify email address in your profile
Check spam folder for Stripe emails
Add [email protected] to contacts

Monitor card expiration:

Set calendar reminder 1 month before expiration
Update payment method proactively
Check Billing dashboard for expiration warnings

Code Examples

Complete Subscription Flow

// Full example: Subscribe to a tier
import { loadStripe } from '@stripe/stripe-js';

// Initialize Stripe (use your Publishable Key)
const stripe = await loadStripe('pk_test_YOUR_PUBLISHABLE_KEY');

async function subscribeToDeveloperTier() {
  try {
    // Step 1: Create checkout session
    const response = await fetch('https://nexus.fortiblox.com/api/billing/create-checkout', {
      method: 'POST',
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        tier: 'developer',
        success_url: 'https://yourapp.com/success',
        cancel_url: 'https://yourapp.com/cancel'
      })
    });

    if (!response.ok) {
      throw new Error('Failed to create checkout session');
    }

    const session = await response.json();

    // Step 2: Redirect to Stripe Checkout
    const result = await stripe.redirectToCheckout({
      sessionId: session.id
    });

    if (result.error) {
      console.error(result.error.message);
      alert('Payment failed: ' + result.error.message);
    }
  } catch (error) {
    console.error('Subscription error:', error);
    alert('Failed to start subscription process');
  }
}

// Usage
document.getElementById('subscribe-btn').addEventListener('click', subscribeToDeveloperTier);

Handle Successful Payment

// After redirect back from Stripe Checkout
// URL will contain: ?session_id=cs_test_xxx

async function handleSuccessfulPayment() {
  const params = new URLSearchParams(window.location.search);
  const sessionId = params.get('session_id');

  if (sessionId) {
    // Verify session with backend
    const response = await fetch('https://nexus.fortiblox.com/api/billing/verify-session', {
      method: 'POST',
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({ session_id: sessionId })
    });

    const result = await response.json();

    if (result.success) {
      // Show success message
      showNotification('Subscription activated! Welcome to ' + result.tier + ' tier.');

      // Redirect to dashboard
      setTimeout(() => {
        window.location.href = '/dashboard';
      }, 2000);
    }
  }
}

// Run on page load
if (window.location.pathname === '/success') {
  handleSuccessfulPayment();
}

Check Subscription Status

// Check if user has active subscription
async function checkSubscriptionStatus() {
  try {
    const response = await fetch('https://nexus.fortiblox.com/api/subscription', {
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY'
      }
    });

    const subscription = await response.json();

    // Check status
    switch (subscription.status) {
      case 'active':
        console.log('Subscription active');
        return true;

      case 'past_due':
        console.warn('Payment failed - please update payment method');
        showPaymentWarning();
        return true; // Still has access during grace period

      case 'canceled':
        console.log('Subscription cancelled');
        return false;

      case 'incomplete':
        console.log('Payment pending - please complete payment');
        showPaymentPrompt();
        return false;

      default:
        console.log('No active subscription');
        return false;
    }
  } catch (error) {
    console.error('Failed to check subscription:', error);
    return false;
  }
}

Update Payment Method

// Get Stripe Customer Portal URL to update payment
async function updatePaymentMethod() {
  try {
    const response = await fetch('https://nexus.fortiblox.com/api/billing/portal', {
      method: 'POST',
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        return_url: window.location.href // Return to current page
      })
    });

    const { url } = await response.json();

    // Redirect to Stripe Customer Portal
    window.location.href = url;
  } catch (error) {
    console.error('Failed to open billing portal:', error);
    alert('Could not open payment settings');
  }
}

// Usage
document.getElementById('update-payment-btn').addEventListener('click', updatePaymentMethod);