Same thing for me. I went from a Note 20 Ultra to S21 Ultra, and every MMS or group chat in the stock messaging app comes in with no="" subject="">. My wife went from a S10e to the S21 and hers doesn't do this. We are in some of the same group chats and her phone doesn't show this and mine do. Some of the older threads on this topic stating it is from the senders phone or network are since it doesn't happen on my wife's S21 and it does on my S21 Ultra in the same group chat. ... View more