You are aware that the teller gave you back too much money when completing a banking transaction.

Honestly, I would  give the money back and if you want my opinion honesty is like the most important thing. Think about it, if everybody would act this way, our beautiful world would be in peace. I try to act the best I can while I can. If if it happened to you. Let's say you own a store and you gave too much change to a client. Like lets say 20 dollars, how would you actually feel if your client brought you back the money. Also I believe that stealing is wrong.