cancellation of contract

I phoned to cancel my contract but the call volume was too high. Then I phoned again later but still there was a high volume of callers. when I phoned the third time, the automated voice informed me I had exceeded my calls to the center for the month and have to phone again after the second of the next month! Seriously? By that time they have debited my account again. The voice did inform me to email to customer care with my query. What if I do not have an email account? Could someone please respond with a solution to this problem. Previously when I did call to cancel this account, they could not find it on the system. Only when I cancelled the debit order, was I notified the account was in arrears. Then somehow the account was found.