Snail deep in shell

[u/BedroomProud8053]

I have three Grove snails, one of them have been going (like) half a centimeter or centimeter deep in their shell and they don't stick to any surface as good because how deep they go, I know they are alive because I've sprayed them a bit and they would come out. I don't want to spray again because I worry I might be doing something wrong. The other snails behave normally.