Unable to retrieve my Trade in Credit Card

I tradet in a computer for a new computer. The procedure to refund me my money for the old computer is now in work since Mai and no end inside. This is the worst customer service I have ever dealt with. it seems like i get the go around with every mail I received. Halleluja I can see a check on my webside,but it was forwarded from Customer Care, but I cannot open it. Talking to Trade in Department is useless because there is no communication available. Hopefully this complain brings somebody from Dell on his feet to figure out how I can access my Crédit Card.