So a while ago, I got an error saying

"Script 'Cache' line 80:RGSSError Ocurred.

failed to create bitmap"

I don't know what the cause of this is, so I wanna know if anyone knows how to fix it.

Does this line look EXACTLY like this?

@cache = {} if @cache == nil

EDIT: actually, it's more likely another script is causing the problem and not clearing the bitmap correctly...

We need more information. What were you trying to do when the problem appeared? If there's no script manipulation on your part, then which scripts are you using? One of them must be the cause of the issue - try to remove them one by one until the problem disappears.