When I try to send text messages my phone tells me they aren’t delivered, but the recipient receives the same message multiple times
Best answer by Mohammed
The issue is related to iMessage/IOS and the number change not being detected following a port.
Try the following:
1) Turn off iMessage (Settings > Messages)
2) Restart your phone (by pressing and holding the on/off button)
3) Tap Settings > Phone > My Number and confirm that it is correct.
4) If it is not correct, please enter the correct number
5) Turn iMessage back to On (Settings > Messages)
6) Finally, go to Settings > Messages > Send & Receive and see if the correct number is displayed under “Start new conversations from:”.
This should fix the issue.