Hey guys I need a little help.

It's getting really damn hot in country, close to 92F in the shade.

The vivarium where I have the BRB is reading 88.2F on the hot side and for some reason the supposely cool side is reading 87.3F(night) till about 89.2F(day)

Humidity roughly stays from 82% till about 90%/91%

How can I cool the vivarium?
My budget is very limited.