Where is my refund?

For Christmas, my dad bought me a Dell Inspiron 15 7537 laptop for college. This laptop ran for a few days, and then gave out. It took me two weeks to get Dell customer support to play nice and send me a replacement with a return slip for the original. The replacement, however, had the same issue. So, a few weeks later, I got a very nice man to cooperate with me and send me two return slips for the laptops. Why two? Because the replacement didn't have a return slip for the original like customer support had told me it would. I finally got the dang laptops sent off. A few days after, my dad received an email that the laptops had been returned and the refund would start being processed. The message said that it would take about 6 to 17 business days to process the refund. It has been over a month since he received that message and there is nothing. Now I am sitting at my dads desktop, ripping out what little hair I have because Dell customer support is not helping me in any way to find out if the refund is going through or not.