Hi just wondering if he’s warm enough, I have 2 Russians and my larger 6yr old hasn’t eaten now for 2wks but she is active. This time of year is very confusing I think for a hibernating species and I think nature takes over. I would just make sure he’s warm to touch wake every morning and soak for 15 to 20 minutes in warm water . Hopefully after that if you offer food he might eat. Someone with more knowledge will help you out soon