A payment made through a bank transfer or a local payment service does not automatically update your app just because the app shows payment instructions.
For a manual workflow, ask the builder to create an order with a reference and an awaiting payment status. An authorized administrator checks the payment in the actual payment account, then marks the matching order paid. Record who confirmed it and avoid confirming the same payment twice.
Do not let a customer mark their own order paid by changing a page field. Any resulting access grant belongs behind a server-side check.
Automatic confirmation needs an integration supported by the specific payment service, including authenticated events or a reliable payment lookup. Check those capabilities before building. A local system such as CliQ should not be described as integrated merely because the app can display its payment instructions.
This is separate from the built-in checkout and its purchase-check helper. Money, refunds and settlement remain with the outside payment service.