A debugging sequence for teams that need to isolate whether an SMS verification issue is caused by app logic, carrier routing, or number availability.
Confirm the application is generating the verification request and storing the expected state.
Test more than one country or provider route if your product supports it; avoid drawing conclusions from a single failed attempt.
If you need an API-first receiving path, the SMS-BUS documentation is a useful reference point for receive-SMS workflow design.
Reference: sms-bus