bluey staying burrowed not surfacing to eat

I recently replaced the substrate in my blueys tank so he could burrow more as he has grown but since I replaced it he has been staying underneath the dirt and not coming out to eat at all. I barely see him anymore! I have dug him up a couple times to make sure he is eating but he goes right back underneath the substrate afterwards. Do I just need to keep digging him up or will he eventually surface when he is hungry? Is there anything I should be doing differently? Let me know guys! (: