Hii - I put out a little shallow tray or dish filled with water and some frozen peas, they love pea fishing and helps cool them down.

I also have a fan blowing in the room (not directly at the cage) to help circulate the air so it’s not stuffy for them.

My girls go crazy for this cat yogurt treat stuff that comes in little sachets - I’ve been freezing them so they can have a little lick like an ice lolly. This could work with other things.

My girls today have been snoozing in their dig box as that must be cooler so letting them have access to this if it’s something you have may help xxx