Fragglebuster

Hi Stef, Yeah I turned it on it's side to get pics of the "fuzz".

Can anyone help please? My two snails have been inactive for over a week now. I initially thought they were dead, but there was no horrible smell and when I touched the bit at the bottom, they seemed to shrink even further into their shells. However I have noticed some white "fuzz" forming and Google doesn't seem to give a definitive answer. Are they actually dead? Hibernating? They were very active when we bought them several weeks ago.