MTN, Yello *****

After I've been a loyal customer for more than a decade, paying my contract on time every month, I found in April that I'm unable to connect to the internet suddenly. It took me more than dozen calls, some over an hour long as I was getting transferred from one clueless call centre agent to the next, and 2 weeks to finally hear MTN decided on their own, without any communication, to cancel my contract. Then all of a sudden months later MTN puts a debit order through on my bank account in September. I reversed the debit order, as I no longer have a contract with them from the incident in April, and now they are threatening me at the end of November with a "final notice" email.