Need Advice re Debt Collection Dispute

Two months ago, I got a letter from a collection attorney about an overdue debt. Thing is, it was for a credit card that I never owned. So, two weeks later, I sent a dispute letter to this collection agent and asked them to verify the debt. A month goes by and I heard nothing from them. One month ago, I sent a follow-up letter stating that the 30-day period for them to verify the debt had elapsed, and as such, I consider this debt to be invalid. Also, I demanded that they remove the debt from my credit report. I even sent a statement to the credit reporting agency saying that the debt was invalid and that the collection agent had not sent me any verification.

As of today, I have not received any further correspondences nor communication from the collection agent about this debt. However, the debt is still on my credit report. What is my next step?

http://forum.freeadvice.com/

It has a section regarding debt collection.