Hi, i'm a first time ball python keeper. but has kept a retic python some 7 years ago.
Maybe a few things to check.. humidity? A large water bowl for the snake to soak itself? and maybe something coarse like a rock or wooden branch/log for it to kinda slither and srape its old skin away? (i put a wooden log in my retic's enclosure previously when i know she's about to shed).

Hope this helps!