Can’t add gmail to my iMessage

Check that the gMail address you want to add to Messages is listed in Contacts, on your own contact info.

(If needed, "edit" your entry to add the eMail address)

To select the phone numbers and email addresses you want to use with iMessage,

go to Settings > Messages > Send & Receive,

then choose from the available options below “You can receive iMessages to and reply from.”

All the best :-)

For iPhone using iOS 17: Apple Support's online article: Set up Messages on iPhone - Apple Support

says:

1. "Go to Settings  > Messages, then turn on iMessage.
2. To select which of your phone numbers and email addresses you want to use with iMessage, go to Settings > Messages > Send & Receive, then choose from the available options below “You can receive iMessages to and reply from.”

Learn more about iMessage. "

What happens when you try the method given?

You might want to check your phone is updated to the newest compatible iOS version: ie: You can check in Settings > General > Software update.

If you still need help, please let us know which iPhone model you are using, and which iOS version is installed.

See what to do: If you can't turn on or sign in to iMessage or FaceTime on your iPhone ...

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