I had a similar problem in my new house I’m building , thought I had mice but traps with chocolate caught nothing , it was hiding nuts in different places , so got a squirrel trap out , nuts disappeared but trap not tripped , I ended up getting a trail camera to see what it was , it was 2 mice , put peanut butter in the traps , both dead next dayTo me it looks like something bigger than a mouse, have you been near some squirrels that have been coming and going?