Refund problem

I've been on the phone with the refund desk 4 times concerning a return of monitors.  I was assured by the sales department that the monitors I ordered would be non reflective. When the monitors arrived, the were super reflective, and I needed to return them due to the lack of knowledge of the sales staff.

I was assured by the refund department I would receive a full refund, including shipping fees.  When the refund was received, it was split between 2 credit cards, not refunded to the original credit card, and the shipping fees were not refunded.

Further calls to the refund department have been a waste of time.  Once I was simply disconnected, twice I was promised a call back from a supervisor.  I have heard nothing from the Dell refund department. 

I can assure you, Dell, I will never again purchase a Dell product, and I will tell everyone I know about your lack of follow through, ill-trained sales staff, and rudeness of the help line. 

How can I get the full refund, as promised, and get the refund office to use the appropriate credit card for refund?