Billing and bad service

I tried to cancel one of my contracts with Telkom Mobile (8ta) last year. I kept sending numerous emails with the cancellation form to different addresses to which there was no response. I assumed the contract was never cancelled as I never received any feedback and I kept getting debited for it. Yesterday I went to make a sim-swap for the same sim card, and I was made aware that the line was blocked. I paid the requested R35 and was told that the sim would be operational from 00:00. This morning when I checked, the sim was still inactive. I called the helpline (081180) and they told me that I have to go back to the store as they can't unlock it from their side. I don't have time to keep going to the store, so I decided to call them instead to find out what is happening. I've been calling the whole morning ***) since 09:00 and the phone just rings without anyone picking up. I need to know why I wasn't made aware that the line is blocked? Why it wasn't cancelled as per my request? Why I've been paying if the line has not been working?<br>