⚙️ Automated Stripe Failed Payment Recovery (with Postmark + AI Email Generator)

Recover failed Stripe subscription payments with AI-personalized emails sent via Postmark.

📝 Template Description

Recover failed subscription payments automatically with Stripe, Postmark, and AI.

This workflow listens for Stripe invoice.payment_failed webhooks, checks that the event is related to an auto-charged subscription, and then automatically sends a personalized email (generated with AI) to the customer. The email is polite, branded, but also urgent — encouraging the customer to pay quickly and avoid service cancellation.

🛠️ How it works

1. 📣 Webhook
   Listens for Stripe webhook events. Make sure to connect it in your Stripe dashboard (see setup below).

2. 🧹 Filter (Guard)
   Ensures the event is indeed an invoice event and filters out unrelated webhooks.

3. 💡 Code Node
   Extracts useful fields (firstName, lastName, customer email, amount, currency, invoice number, hosted invoice URL, subscription description, account name).

4. ✅ If Node
   Verifies that:

   • Event type = invoice.payment_failed
   • Billing reason = subscription_cycle
   • Collection method = charge_automatically

   👉 This ensures only recurring subscription invoices with auto-payment are processed.

5. 🤖 AI Agent + OpenAI
   Generates a ready-to-send email JSON (to, subject, HTML body) using the extracted Stripe data.
   ✍️ You can customize the prompt here to match your brand’s tone of voice and style.

6. 🧩 Code Parser
   Parses the AI model’s JSON output into fields (to_email, email_subject, email_body).

7. 📧 HTTP Request (Postmark)
   Sends the email using Postmark’s API.
   You’ll need your own Postmark Server Token, From address, and Message Stream.

🚀 Setup Instructions

1. Stripe Webhook

• Go to Stripe Dashboard → Developers → Webhooks.
• Click + Add endpoint.
• Use your n8n Webhook URL (from the Webhook node) as the endpoint.
• Select event type: invoice.payment_failed.
• Save and deploy.

👉 Example docs: Stripe: Listen to events with webhooks.

2. Disable Stripe’s Default Failed Payment Emails

• In Stripe, go to Billing → Settings → Customer emails → Manage failed payments.
• Turn off “Failed payment” emails under the Revenue Recovery section.
• This prevents customers from receiving duplicate or conflicting emails.

3. Postmark Setup

• Create a Postmark account.
• Add a Server and copy the Server API Token.
• In n8n, add Postmark credentials with this token.
• Configure:
  • From = your verified sending email (must be verified in Postmark).
  • MessageStream = typically "outbound" (or any custom stream you set up).

Docs: Postmark API overview.

4. OpenAI Setup

• Add your OpenAI credentials in n8n.
• Attach them to the OpenAI Chat Model node.
• You can modify the prompt in the AI Agent node to fit your company’s style.

✨ Customization Tips

• Update the AI prompt with your brand’s tone of voice (friendly, formal, playful, etc.).
• Adjust the HTML email design inside the prompt (button colors, footer, etc.).
• Add extra guard conditions (e.g., only trigger if invoice_amount > 0).
• Change the sending service: replace Postmark with Gmail, SMTP, or another provider.
• 💬 Or talk to our Billing Recovery Experts at flycode.com for hands-on help.

✅ Outcome

Whenever a customer’s subscription payment fails, this workflow:

• Detects it instantly via Stripe
• Generates a polite but urgent recovery email
• Sends it automatically via Postmark

Result: Fewer cancellations, higher recovered revenue, and a smoother customer experience. 💸💌