Hides are too big , enclosure is too big, basically you need to get started again from scratch.

BP are are not very forgiven with husbandry issues.

Here is what I recommend to get back on track ASAP

Get a 6 quarts tub

Aspen bedding

1 Plastic flower pot saucer for hide (6 inch in diameter)

UTH

Thermostat

Provide a temp of 86/88 on the warm side.

Leave the animal ALONE for a week so it adjust to his new setup (no handling until the animal eat successfully for you)

Once the week is over offer a live mouse (right now the animal feeding is the priority, switching to F/T is only secondary). Place the mouse in the tub (do not feed outside the enclosure)

When the animal reaches 200/250 grams you can switch to either a 15 quarts tub or 10 gallons tank, the 40 gallons tank will be fine when your snake is an adult but until than the enclosure must fit and meet your BP's need.