Message not sent. Phone number formatted incorrectly

[Crate8627]

I recently switched from EE to O2, but decided to keep my old number using a PAC code. At the same time I have also changed from an iPhone to a Pixel.

O2 have successfully transferred my number which works great when messaging other android devices. However, if I try to message any of my contacts that have an iPhone I receive the error "Message not sent. Phone number formatted incorrectly". I believe this has something to do with iMessage as my number was previously connected to it. I have since removed it from iMessage but the error persists.

[pgn · Accepted solution]

Seen this happen on SMS short codes, eg for INFO or BALANCE or Priority rewards: delete the number from your phone address book, key it in anew, @Crate8627.