Corn Not Eating

Hey guys

I have a young corn snake (About a foot and a half long, not a hatchling) that has not eaten in about two and a half months. I've tried putting him in a separate room while he eats, I've tried force feeding him (He won't take that at all v.v) and I have even tried the lesser known method of taking brain matter from the mouse and enticing him with that.
He just won't eat.

Help?

Are you using live or ft? What were you feeding before he stopped? What's your setup: temp, hides, room temp, bedding? Is he wild caught or captive? Has he lost weight?

I generally use f/t, but in this chaos, I have also tried live. No results.
Setup is in a 20 gallon tall tank, that usually runs at 80*F. Hides are a hollow stone filled with damp moss and a hollow half log, bedding is aspen.
He is a captive bred, and he has lost a bit of weight and is visibly thinner than he was when I got him.

Few more things to try:

1/Stick him in a small rub with food and leave him overnight, my baby takes it near enough instantly in a tiny rub where anything bigger it would prefer to cruise around in.

2/Rub the mouse in either tuna or chicken fat to "spice" it up a bit.

3/Make sure the mouse is warm when attempting to first feed.

Braining is supposed to be a good way to get a response but you have tried that. I am by no means an expert but these are the things i have read in my short time owning a corn snake.

I think number 1 above should be stick him in a small tub with the food. A small tupperware container with ventilation normally does the trick for me. Good luck.

I've tried putting him in a small, opaque tub with vent holes with the mouse for about thirty minutes, but I'll definitely try leaving him in overnight. There's no risk of him getting too cool?
And thanks everybody for the suggestions :3

I put my babies in a small tub inside their tanks over night. Just dont put it on the hotside.

He'll be fine in the small tub overnight.

Alright, put him in the tub for tonight.

Hopefully that works. If it doesn't, in a few days try a boiled pinky. Literally boiled. I haven't done it (haven't needed too) but an experienced breeder on another forum figured it out and aparantly it works for corns.