cant maintain a high temperature in glass cage

[CatandDiallo]

I have my thermostat probe right above my substrate (cypress mulch) behind the hide.

I'm surprised no one mentioned this yet. The thermostat probe should be directly touching the heat source. I.e, the probe should have been placed on the bottom of the tank, with the heat source taped ON TOP or it, or you can use tape (aluminium tape works best) to tape your thermostat probe on top of the heat source.

The thermometer probe should be right above (or just a tiny thin layer below) the substrate.

Other then that, I was going to suggest thinning out (A LOT) of your substrate, but someone has already mentioned this.

Good luck.