services termanated,waiting on refund for over payment

I termanated my services with Direct TV in July. I had recived serval invoices saying that I am due a credit. But never recived check in mail. Spoke with customer service on Aug. 27, 2008 and was told that It takes 6-8 weeks to get my refund. I was also told that the 6-8 weeks starts on Aug.1, 2008.  The Lady told me that is there policy and nothing she can do about it.  Now let me tell you, If I am ONE DAY LATE with my payment to them, my service is cut off right then and there. If it all possible, please let me know if there is anything you can do to speed this up.  I fill there should be a law on how long a person money is held. and if it is held, then there should be intrest add to it.
Thank You,
Dennis Howard