Defective Latitude 10

On Saturday September 28th 2013 I placed a phone order for a Latitude 10, the top model. I had missed out on the promotional option when I ordered my XPS 15 a couple days earlier so I was trying to see if I could add it now, it was a $200 off offer. I placed the order and was promised I would get the $200 off the sale. Well because the website specs for the 3 versions of the Latitude were very confusing and misleading, I realized I wanted the mid priced tablet. So I called back and we changed the order. A few days later I noticed I was charged the full price of $619 with tax. I called and was told I was getting a $200 coupon instead, okay that was fair. A week later the tablet shows up, after a day one of the speakers failed. I called to set up a return and I am told that that order was cancelled and they couldn't help me until it was invoiced. Well it has been a month and a half and they still have not replaced the Latitude. I have provided them with everything they need including a copy of the bank statement for $619. They still do nothing. Recently they said they were going to send a Fax to my bank to clear this up but I see nothing in my bank statement. Being a first time Dell costumer I can say I am not impressed. I have been on the phone for probably 50 hours now. They constantly bounce me around on the phone and dodge the issue that there was a mistake made on their end, I wish they would take the responsibility and replace my defective tablet.