I'd remove the sponge, and never, ever put it back in. Sponges are bad news. You can try to spray the cage, it might help. I'd try to move the cage into a steamy room like the bathroom and run the shower hot for a while. Close the door and let it sit in there for a while. Not sure if it might be too late, but it is worth a shot. Good Luck
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KJ Vezino
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