When I go ( on my ipad) to settings/messages/send receive/add an email address, I add the email address I have on iPhone, them came the message “Unable to veryfy email because it is already in use”. Can you help on how to sinc messages from iPhone to iPad?
Try to set your iPhone to factory settings, then configure when it ask to setup emails after reboot. This is what I did when I can’t sync my emails and contact to iPhone.
John Holmes, ipad cases designer