i want 52.01 back on to my card (walmart prepaid i have let them know i want it back) very unhappy with the product. and they have abbused the info i have provided

We just got a Redbox put in our Wal-Mart and decided to check it out since it was cheap. We used our debit card and was charged correctly for 2 movies. We returned the movies the next day like we were suppose to. That was the first time we had ever used a Redbox. Well 2 or 3 weeks later we find a charge in our bank account from Redbox for $51.36. We called them and they said they could not even find our debit card in their computer and that was the only way that they could find out anything. RedBox is a rip off. They don't even give you a receipt or tell you what amount you are going to be charged. We called our bank and they said we could fill out an affidavit for unauthorized charges and they would investigate it so thats what we are going to do. We told them that and then they started like well we are going to send your bank a letter stating that we will release the funds to be put back into your account. They know they are a scam. They would not be willing to do that unless they knew for a fact that we were telling the truth. They knew we were right about it. That is the only reason they said they would do that.