Why are payments appearing twice?

Duplicate payments usually mean the same purchase was reported more than once.

What actually prevents duplicates

In the current backend implementation, duplicate protection is based on a stable transactionId.

• If you send the same transactionId again, Flowsery can update the existing payment record instead of creating a new one.
• If you send different IDs for the same purchase, Flowsery cannot deduplicate them reliably.

Common causes

• Reporting a payment from both a provider webhook and a custom success-page call.
• Generating a different transaction identifier on each retry.
• Mixing a connected payment-provider integration with manual Payment API calls for the same purchase.

Fix it

Choose a single reporting path per purchase:

1. Use the connected provider integration, or
2. Use the Payment API with a stable transactionId

If you use the Payment API directly, prefer the real backend field names such as visitorUid and sessionUid.