My wife just upgraded to a new iPhone. She tried twice to transfer from old iPhone 8 to iPhone 12 but it didn’t take so used the iCloud backup transfer.
In making this migration to the new iPhone, one of her Messages threads got munged so that posts to/from her new iPhone were not visible on that lengthy thread.
Not knowing what it would do LOL I changed the Messages settings to use just her cell number for send and receive and now all seems to be working.
So a couple of beginner questions:
Any obvious reasons why she momentarily was kicked off that thread?
Any advice about whether to use more than one’s cell number in the “Send & Receive” settings for iMessages?
Is there a way to mark messages as unread?