Contact name changed and I didn’t change it
I had someone set in my phone as the name I wanted them as and a pic and then went back into my phone few hours later and name and picture had been changed. What’s going on?
Perhaps, the person on the other end is using an iOS feature called "Share Name and Photo", which enables them to edit their name/display picture from their end. When they message/call you ... you get the updated name/picture.
Read about that feature here: How To Set And Share A Custom iMessage Name, Profile Photo On iPhone Or iPad - redmondpie.com