DELL
Money taken 2 twice from credit card for single purchase

I have purchase Dell laptop warranty extension. The sales executive asked me to do payment through credit card. I paid using the telephone transaction as per the service executive. The service executive have charged me twice from my credit card. When I contacted the Dell customer care they said that they will refund the ammout to me.

But, even after two months they have not refunded the money.

I have called 100 times the customer care but every time they are connecting me to the same sales executive and every time the service executive says that he is working on my request but no action taken till date.

Can any one kindly tell me how to escalate the issue.