Your tank hasn’t been cleaned properly. I can’t be sure what the exact problem is, but I’d place Lumineon and Shellos in a temporary container with new water, then completely scrub and clean their tank
And no soap! Soap is bad for sensitive skin and especially for gills.
ok. i had to look this up, because this seems just too ridiculous. and wiki does not disappoint: “…
the hognose snake will often roll onto its back and play dead with its mouth open and tongue lolling, going as far as to emit a foul musk from the cloaca.
Emission of cloacal musk is considerably less likely than in many other
species. If the snake is rolled upright while in this state, it will
often roll over again as if to insist that it is really dead.”