First time ever this has happened to me

So I had a bunch of pelts for the trapper, including a nice moose pelt. I arrived at the location near Elysian Pool and he greeted me like he normally does. Then I removed the moose pelt from my horse and walked up to him and he suddenly runs away and “WITNESS: Trespassing” has appeared and now there’s a crime reported. Like what? WHAT?? Tf did I do? Has anyone else run into this?