Account Cancellation

I went to Telkom in Centurion mall on the 27th of May to cancel my account, filled in the discontinue papers, made a copy of my ID. Somehow they never filed the papers for cancellation and now I am still getting billed for a service I'm not using. Then I went to the same Telkom in July, had to fill in the same papers and give another copy of my ID. They probably lost these papers as well. Why must I pay for the mistakes of a company? Why don't they have an online cancellation facility so I can have record of the cancellation request? Doing things on paper like its 1950. Telkom is the most unprofessional and pathetic service provider in South Africa. I won't pay for the mistakes of your unorganised organisation. I won't be held accountable for a service that had to be cancelled 2 months ago because your employees can't handle paperwork.