Hey, you've been a member for many years and you still don't know that there is a proper section on CoinTalk to post this sort of thread? Paper Currency forum! Also, it's not a mint error. It would be a BEP error. There should be a premium for that issue. It depends on what a collector of that printing error would be willing to pay for it.
The mint doesn’t print paper bills, only coins. Only the Bureau of Printing and Engraving does. Yes, it’s an error. Here is one of mine. Yours is “Partial Offset printing back to front”.