As hopefully you know already (from reading the care-sheets here?) BPs need more warmth than 82* (where they are actually laying, not what the thermostat says
in order to achieve that, but what the snake actually has available), so this needs fixing ASAP or you'll have a sick BP & a vet bill too. The cool side should be 77-80*
and the warm side should be about 87-88* (not over 90*), & this is why we suggest setting up a cage & running the heat for at least a week to test it out before trying
to have a new snake live in it. It takes time to acquire the right equipment- if you don't have it locally, you can find most things online, from places like Reptile Basics.
Hope you get right on this...but in the meantime you can easily provide more warmth with an overhead red or black* incandescent bulb in a reflector-type fixture & for
SURE run it with a rheostat (lamp dimmer) at the very least. *Most snakes don't like bright lights, thus red or black bulbs give heat & far less light...can be used over-
night too, for now, until you get a more appropriate heat source (etc) figured out. Every situation is different....sounds like your room is cold (?) making it harder to
keep heat in the cage.
https://www.reptilebasics.com/
https://beanfarm.com/