I'm not sure if you are experiencing the same problem that I had, however here was my issue and fix 😊
Imessage would be locked at waiting for activation and would route all imessages through an email I had associated with my apple ID. However i wanted it to route it through my phone number instead, which couldnt be inputted at all by any means that i tried and all the fixes id googled so far got me nowhere 😠.
When looking at the facetime settings, it showed me a phone number that it was trying to use to verify the activation. This was not my current phone number. It was trying to use the phone number i had recieved when i purchased my iphone (i had instead decided to transfer an older number to this device).
Therefore it was trying to verify the activation with an incorrenct number (maybe it doesnt even exist anymore) as it didnt authenticate my new telephone number with my device.
The fix?
Log into your apple id online and within the settings of your profile you are able to allocate your actual phone number to your apple id and then save these settings
The next time i looked at imessages or facetime settings, sure enough my current phone number was autoregistered and the 2 applications were verified. 😁
HOPE THIS HELPS! 🙂