I have the latest iphone os and big sur 11.4. Both the latest but int he past week I've had problems with messages not syncing across phone/imac and also photos not syncing. nothing has changed.......1 group chat that i have in messages is trying to send as mms or whatever it is called........showing a green bubble instead pf its usual blue bubble......then it just does not go though. Both other people in it have iphones and it is usually sent as blue..........super weird........anyone else experiencing this?