Try a different humid hide that is covered (yours are transparent). The location of the entrance is not a big deal. I also drilled holes at the top of my ball python hides and he uses them without issues. It could be because he feels too exposed on there and ditched it.
Another way to keep humidity up is to switch to a substrate like coco fiber or cypress mulch. I use coco fiber bricks (Not the bags) for my skink and it holds up humidity for days. You can also boost humidity by using a humidifier with or without a timer. In addition, using plexi glass to cover part of the mesh lid or wet towels helps as well.
Your cool side is too cold as some had already mentioned.
I'm not a fan of red lights for night time use. Red light or infrared light is a controversial topic. Some claims that they can see the light and it stresses them out while others don't think so. There are better options out there, imo, that does not potentially risk stressing out your snaks like the use of a CHE that emits no light and only heat. However, CHE is extremely hot and should not be used in small enclosures like a 10-20 gallon tank. Sometimes an easy fix is to move your tank in a room that has 77-80 F room temp.
A lot of good advice has already been given to you so I have nothing else to add.
I do want to state this for any new snake owner or potentially new snake owner reading this (And perhaps for your next pet): One should NEVER go into pet ownership unprepared or "not knowing what to expect." Plenty of research including how to tell what a normal or stressed out animal would look like should be ingrained in one's knowledge before obtaining said animal and try to wing it. That will only create more stress on yourself, the pet and increase the likelihood of preventable mistakes. There are books and numerous articles available for reading. Pet ownership is a long term homework assignment: keep reading, keep learning and preferably before bringing the animal home.