Citibank Credit Card Complaint

Citibank Credit card department,

Credit card protection / Debt protection North Carolina

Citibank credit card has been charging me for a service I did not sign up for called Payment Safeguard. They say I signed up for it in - of 2007, but I did not sign up for this service. I requested they send me written proof or a recording stating I signed up for the service. And today, I only got a letter saying I signed up for it in - of 2007, but provided me with no proof.