Not eating, underweight ball python

[newbpowner4]

I have an enchi ivory het clown male ball python that I picked up on December 6th, 2020. On the Certificate of Origin, it states his birthday is July 8, 2020 however, when I contacted the seller again regarding a different snake, he told me the birthday for this boy was actually August 11, 2020. I mentioned the discrepancy but he didn't really address it in a clear way and said "it's not that important" so I dropped it. Anyway, that means that he (his name is Platano) is at least 7 months old, maybe 8.

When I received him, I weighed him and he was only 72 grams. I fed him every 5 days for a few months until he got a bit over 150 grams, then I switched to every 7 days, like my other snakes. He was eating really well for me until recently, striking almost immediately when I'd offer him food. I should mention, he was on live mice before I got him and I feed f/t rats. Didn't really have a problem switching him over to f/t rats either.

Recently he's not being eating as consistently. Like 6 weeks ago, since he was starting to get bigger, I tried to feed him two 10g rats. He ate both just fine. The next week I tried to feed him a bigger rat (~15g) and then another small baby rat (10g) after but he only ate the first one. The next week I tried to feed him just one 23g rat and he wouldn't eat. If I remember correctly, that was the first time I offered him a rat with fur on it. So, since I was still concerned about his weight, I opted to go back to a 5 day feeding schedule. After 5 days, I tried his "usual" smaller one with no fur of about 18g. If I remember correctly, I don't think he ate again.

Then, when I was feeding my other five snakes four days later, my other boy didn't eat his because he was in shed. So just to see basically, I tried offering the rat to Platano since he was due to eat the following day anyway. I planned to stop if he didn't immediately take it, so as not to stress him out but to my surprise, he actually ate it! This was a 38g rat btw, and Platano had was 190g at the time so the rat was 20% of his bodyweight. I considered myself lucky to get so much food in him and I left him alone and everything was fine, he didn't regurge or anything. Since I thought he was fine again I decided to go back to a 7 day feeding schedule.

The next time, I offered around a 25g rat. He didn't eat but he was in shed so I figured that's why. I waited a week, offered a 23g rat. He didn't eat again. Waited 5 days (didn't wait a week because I'm concerned he's still underweight) and that brings us to today. Offered a similar size rat (with fur) again, and he still wouldn't eat. I have 5 other snakes all in the same room, same temps, same humidity and they eat just fine. After he didn't eat 5 days ago, I added 2 paper towel rolls to his enclosure to give him more clutter and hopefully make him feel more secure. I also added a scrunched up paper towel in each hide to make them feel smaller and more secure. He is in a clear bin but three out of the four sides of the shelf he's on are enclosed. So also five days ago, I cut a piece of cardboard and placed it in the front so now he's enclosed on all four sides.

I don't handle him at all anymore except to clean his enclosure/weigh him. I feed inside the enclosure. I have a temp gun that I use to make sure the rats are the right temp. I thaw overnight in the fridge, warm up in a ziploc bag in warm water and then blast the head of the rat with the hair dryer. I'm not sure why he's not eating and I'm worried because like I said, I think he's underweight. I will add a picture so you can see. He has a hide on both the cool and warm side. I have a thermometer for the heat pad on the warm side set to 92 degrees Fahrenheit. I haven't changed the temps or humidity of his enclosure since I got him. I know it's normal for ball pythons to not want to eat every once in a while but I'm so concerned because he looks underweight to me. Please let me know of any advice you have and also, if you think he is underweight too in the picture.

Here's links to photos of him.

https://ball-pythons.net/gallery/sho...hp?i=60224&c=3

https://ball-pythons.net/gallery/sho...hp?i=60225&c=3