HCA: Hermit Crab Association

I recently bought three crabs, i have all the supplies and correct size tank and there has been no fighting amongst them but one of my crabs has been burrowed for days and doesn’t seem to be molting because it is moving around and digging tunnels but it won’t come out to eat or drink, is this normal?

Yep, that perfectly normal. Just being a crab! Chances are they were deprived from being able to dig for months and is just excited to do it again. A good bit of the time molting is the crab digging around to find a good spot to molt.