A Girl from My Class Unfollowed Me

A few months ago, my class group went on a trip, and a girl from my group asked for my Instagram to mention me in her story. I didn’t think much of it and followed her back. Today, I randomly checked and realized she unfollowed me. Now, I’m wondering—should I also unfollow her? It’s not like we’re close friends, but we are in the same group. Would it be petty, or is it just fair? What would you do?