Humid hide help

[nikitab]

So I recently bought some moss and converted a plastic box to create a humid hide for my rt
I've placed it under my che but the inside doesn't seem to be warming up, any ideas to help get the temp up?

 

[Alexio]

Do you have a roof on the enclosure?

 

[nikitab]

I'm getting a new plastic cover tomorrow as I just upgraded his table size and his old one was too small