Delta Airline/expedia, Internet

We booked two airline tickets on the inter net using expedia on sept. 09,2010. We did not receive a conformation email from expedia nor did we receive a itinerary. I did go to expedia web to find out if they had a itinerary on file for me, nothing was found. The next day I called my card company(key bank) to see if my card was charged, no charges were found.

Two day later, I booked the same flight with Orbitz. One week later my bill came in from Key bank with both flights charged to my account. Expedia admit they did not send out the conformation email, but said they could not refund me because Delta Airline would not allow them. Delta Airline agreed to give me a credit if I paid $150.00 for each ticket. The ticket cost $195.00 each