I got my corn snake from Petsmart (yes, I know, PETSMART! They're terrible & I regret it). They gave me this chart telling me when the snake shed & when it arrived at Petsmart. She came at 6/13/19, so my snake should be at least 9 months old. In Maple's entire life, she has only shed about 3 times. She is a healthy weight (I think), & is around the same length as when I bought her (almost 6 months). I'm pretty sure this is bad? Any ideas on what is happening?