Subscriptions that charged twice

The problem

Customers paid for their subscription, but sometimes they were charged twice, and at other times they were left without access even though they had paid. The support team spent hours resolving these cases by hand and refunding money.

The proposed solution

I started from the cause: payment and access were handled separately and fell out of sync when a step failed. I proposed a single flow in which a confirmed payment decides access, and any failure is retried automatically and safely.

What I delivered

• A payment flow in which an order cannot be charged twice, even if the customer clicks several times or the connection drops.
• Account access updated automatically right after payment.
• Clear messages for the customer on failure, with a retry, instead of generic errors.
• A simple panel for support, to see the status of every payment at a glance.

The benefit afterwards

Double payments disappeared, and payment-related support tickets dropped by almost all. More subscriptions were renewed, because access was no longer lost after payment.