v21 acccount help please

flamer_2

I need some urgent advice about a bill I received from V21 on the 1st of Feb. I used the Fast4 service for a few years and then we got broadband with Sky in October 06, so no longer required the dialup service. It was around this time that the members console was locked and i tried everyday for weeks. I had subscribed to fast4 on a 6 monthly basis paying £39.99 and knew the next payment was due in January. As I couldn't access the member console to start the cancellation process, I sent a recorded delivery cancellation letter at the end of November thinking that 30 days notice would be adequate. I had no email or confirmation that cancellation was accepted, and assumed that my account was cancelled as i tried to access the members console where i got the message that my login was not valid. I subsequently cancelled the DD. Didn't receive any emails until i got this bill from v21 demanding £79.97 for 'Services for telephone' for the period of 15-01-07 to 15-03-07.
I haven't used their service since the end of last year ! I don't see how can pay 80 quid for a service that I cancelled via letter because their console was locked, gave 30 days notice as per their terms.

Please advise a confused moneysaving fan

Thanks