Stripe Webhook: Empty IDs & matching issues for returning customers in Backend Workflow

Need help APIs
1

I am trying to automate user subscription tracking in Bubble by parsing Stripe checkout.session.completed webhooks. The goal is to update the User record with stripe_customer_id, stripe_subscription_id, and set is_premium = true..

Current Setup & What Works:

  • Endpoint receives checkout.session.completed webhooks with 200 OK.

  • Search for Users successfully matches the user by email using direct field selection on Request Data.

  • is_premium consistently updates to true.

  • Initial Test Behavior: On first setup, live events left the ID fields blank, but manually clicking Resend in Stripe successfully populated stripe_customer_id and stripe_subscription_id.

The Issue:

  • On live checkouts, stripe_customer_id and stripe_subscription_id evaluate to (empty) on the User record.

  • Server logs show the payload contains the IDs, but for returning customers (who already exist in Stripe and have an old stripe_customer_id in Bubble), it occasionally pulls a previous subscription ID or leaves the field blank.

  • Rebuilt the workflow with a 10-second delay step to rule out database/timing race conditions, but the issue persists.

What is the standard, best-practice Bubble logic to handle checkout.session.completed for both new users (matched by email) and returning customers (matched by existing stripe_customer_id / email) to ensure the current subscription_id always saves reliably?