iReal just all of the sudden won't open.

I get this prompt "“iReal Pro” was purchased using the App Store on another computer. To use “iReal Pro” on this computer, sign in using the Apple ID and password used to purchase it."
Which is untrue. I purchased iReal on this computer. I attempted to sign in to "authorize" iReal on this Macbook and it says "Your device or computer could not be verified. Contact support for assistance".

I have gigs tomorrow and this is really freaking me out. Anyone have this issue?

I can't even update it in the APP STORE because it gives me the same issue.

I've tried repairing permissions and restarting. No dice.