The customer paid at the provider and the invoice still says Unpaid. Almost always, the provider's callback never reached WBAMS.
Check, in this order
- The gateway log
Billing › Gateway Log. No entry means the callback never arrived: the problem is the address registered at the provider.
- The module log
If there is an entry, Utilities › Logs › Module Log shows what the module did with it.
- The System URL
Settings › General: it must match the address the provider is calling, scheme included.
- The provider's dashboard
Its delivery attempts and their responses. A 404 or 500 there points straight at the cause.
Never mark it paid by hand to clear it
It hides the broken callback, and the next payment fails the same way. Fix the callback and let the payment settle properly.
Full guide
The complete reference is When a payment does not land in the WBAMS documentation.