How to re-register iMessage with phone number
I accidentally deregistered phone number with iMessage . How can I re-register that number with iMessage? Thank you!
iPhone 6 Plus
Messages - If you get an error when trying to activate iMessage or FaceTime
Do you have access to another WiFi network where you can try? That has worked for several people.
Try a restart.
Restart your iPhone, iPad, or iPod touch
Try a forced restart.
If necessary
You will need to restore the device to factory settings. Do not restore from a backup made when the Screen Time code was active.
Do a backup and try a factory reset. Then restore from your backup.
Backup - Restore your device from an iCloud or iTunes backup