Unsuccessful message delivery could be for plenty of reasons. Please check the below reasons to determine the problem
- Incorrect number formats
- Missing international codes
- Mistyped numbers
- Expired numbers
- Network overload/failure
- Absent subscriber (phone switched off)
- Memory capacity exceeded
- Insufficient credit
- Illegal subscriber
- System failure
- Sender ID not registered
- Restricted SMS content
- Restricted networks/countries
- Invalid/noncompatible SMS length
If you cannot determine the problem on your own, please reach out to support@cequens.com with the error code.