Why am I getting a group text from 1 person , please helpppp.

[AC Question]

Recently I have been texting my boyfriend...our numbers have stayed the same nothing has changed...but the fact that when he sends me a message it comes as a "group text message," but it'll just be the two of us...I have two message threads..a regular one then a "group text" one...I get messages from either one and now my messages are out of place because of two message threads. I've tried deleting the messages, his number and readding, I even restarted my phone and still get both message thread...can someone please help.