If you have had similar problems like this before with a Ball Python, the cause might be environmental.
Did you thoroughly clean and sanitize the tank and accessories before adding this snake to it?
Do you use any harsh chemicals for cleaning inside, outside, or around the tank or its accessories?
Do you provide tap water, filtered water, or bottled water for the snake?
Have you been using a wood, paper, or fabric substrate for the snake? When has it last been cleaned?
Exactly what are your temperatures? Hot spot? Cool zone? Ambient versus substrate temps? Water placement?
Do you wash your hands thoroughly between handling pets of same or different species? Some parasites can move between species.
Any (decent, quality) pictures you could provide of your set-up and the snake would be helpful.
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Lincoln, NE
0.1 Pastel, 1.0 Pastel het Pied, 0.1 Pied, 0.1 Cinn, 1.0 Black Pewter, 1.0 Woma (hidden gene?), 0.1 Yellowbelly
2.0 Normals, 1.0 Thayeri, 0.1 Thayeri X Alterna, 0.1 crazy cat, 1.0 husband