Family Dollar

I went to Family Dollar tonight to purchase some items. Pepsi was on sale for $1.00.. I bought 8 bottles and some other things. When I was rung up the total was correct. The debit/credit machine wasn't working. The cashier suspended the transaction and sent it over to the other register so I could pay. When I went to pay the total was not correct. I was charged full price for the soda. I went back with the receipt to tell them. They went to scan 8 bottles of soda to return them for the transaction. It came up at the sale price for the return. They gave me $9.09 back and then told me I had to re purchase the soda for $9.09. They were arguing with me that it was correct and took the 9.09 back. I was charged $1.80 for each bottle. For total of 14.40.. I'm very upset that they did that to me.