Extremely bad service. Been trying to cancel for a year

For about a year I’ve been trying to close my telkom account. About a year ago I went into telkom to change my banking details as they had changed. They then continued to debit an account I hadn’t been using or had no money in which accumulated R2500 of returned bank changes. Because they continued to debit the wrong account my telkom bill wasn’t paid and returned fees R2200 on telkom a side for all the months. When I went into absa to close my account I realized that all these charges were added even though I had gone in to change all my details. I then proceeded to settle my account and cancel it. Went into the store and they said I must do it online. I did so at the shop and on my profile my account wasn’t there and the assistant told me if it’s not on the website it’s cancelled and settled. I thought that was the end of it. 2 months later I then got a bill not reflecting the amount I had paid and also an additional 2 months of debits. Every time I call telkom I get transferred from one person to the next. I then got transferred to a very helpful guy who said I just have to email all my info as well as POP to the documentsTM email after which I got a reply telling me I have to call the same help line that put me through to them . I just want to cancel my account but it’s been a complete nightmare.