First, be sure you have at least one hide on each side.
Put the humid hide on the warm side - if your BP will use it. Mine won't.
Some other ideas, put the water dish on the warm side - or add a second dish and put it on the warm side. Cover most of screen top with duct tape leaving holes for the lights, etc. Make sure you put it on such that the snake can't get to the sticky side. You can try misting the back wall of the cage a couple times a day.
For me what I ended up doing (because all the other ideas were too much work and I wanted something easier) is the duct tape idea and I added a Tropic-Aire Humidifier w/ air pump. Problem fixed and all I have to do is refill the Humidifier about once a week.
If you can get your BP to use the humid hide, then that's all you need to do.
Best of luck!
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