My normal often prefers the cool side over the warm side. Check the temperature at the surface of the glass on the bottom of the tank and then on the substrate he/she lays on inside the hide on the warm side. If the temps are right and not too hot, I’d just let him do what he wants. As long as he has access to the warm side he will go when he wants. After my normal eats he will lay in his warm hide for a day or two then he lays in the cool hide or the one I have in the middle. As long as the surface temps are good I don’t think you have anything to worry about.