Sold My Guitar To Guitar Center So I Could Make Rent, And They Gave Me A Counterfeit Bill.

So on Sunday I sold my guitar for $800 at guitar center and they paid me cash. After work today, I went to my banks atm to deposit the money but it would not accept one of the $100 bills. I took it to the window and told them the atm wasn’t accepting it and they looked it over and told me it was a counterfeit.

I explained how I got it, and they gave me a form to take to guitar center and the banker also gave me his business card.

Now I’m short for rent and guitar center is closed tommorow for new years.

What can be done about this, and is it even worth doing anything?