Charged Twice

Last sunday I bought something, I tried twice to buy. The first time, Dell didn't accept because of some validations... ok, the order wasn't placed, I didn't even finish it so, I tried again and, apparently, I did it well... When I saw my Card history, the Twice of the amount was charged. I immediately called my bank, they told me that I can wait few days because both of the transactions were pending. Ok, I waited and chat with your agents. Another thing I did was write emails (two you) non of them were answered and I, already, opened a ticket too because I wanted to know WHY if the first transaction didn't pass, is in my card history...

Today, I called again to my bank and guess what? They told me that YOU guys (Dell) charged twice the amount.

After three days, can someone finally help me out?