Can't see texts sent or received from only one contact

I cant see texts sent or received from only one of my contacts. The number is saved as a favorite and I can see the text thread with 5 text msgs that she has sent to me but can't see them anywhere. It happened when I downloaded messenger app. My contact is not on any block list, I have removed and added and restarted. Oh the other weird thing is I can see texts I have sent and receive her texts only when she is included in a group text but not individually. Can anyone help?