Recently we we have been getting a lot of complaints from our customers, mostly MTN users about delivery issues.
The reason for this failed messages is the DND (Do not Disturb) system implemented within mobile network operators in Nigeria. What this means is that people on that list will not receive any kind of BulkSMS.
More specifically, when it comes to MTN some of the subscribers were automatically put on the DND list and they are required to opt out again by sending ALLOW to 2442, that should enable them to receive the messages again.
Other than sending “Allow” to 2442, there is no way to go around this at the moment.
We have contacted MTN and they are aware of the complaints received from our clients, we are hoping they will be able to resolve/fix this issue soon. We appreciate your patience in the meantime.
Please feel free to contact us for any questions. firstname.lastname@example.org