Telkom stole from me

I have cancelled my telkom account in December 2019, there was an issue like there always is with telkom I then had to cancel again, note that the first time was online through their portal which didn't work so debits never stopped and when I went into the store after a literal pointless back and fourth with the store assistant they then cancelled in store and I got an sms saying it was cancelled,

Since then I have been debited every month which only stopped after I went to the store again this stopped in July 2020, yes I cancelled my telkom contract in December 2019 and Telkom didn't stop debiting till July 2020 through a pandemic which everyone is still struggling through especially with finances.

During this period I needed to get my money back which telkom basically stole from me as they didn't stop the debit even after calling, mailing and visiting the store.

My telkom debit was R818.99pm, after going to the store multiple times a lady calls me from accounts and tells me they can only refund R500 then says she's going to call back puts the phone down and never does, the most recent interaction I had was 2 weeks ago and the same thing happened lady calls me while I am in store says there is a credit notice on my account of R1000 when I asked her how she got to that number couldn't tell me infarct told me the person who did the calculation was going to call me back on Monday 21st of September, Still no call her name was Pretty, I'm no mathematician but R818.99 x amount of months from December till July? how does this math work?

I'm out of options here and don't know what the next step should be this is thievery if a consumer was to not pay Telkom how long would it be before a debt collector calls internet would be terminated immediately.

What kind of customer service is this what kind of company is this how can it be possible that something as simple as stopping a debit or cancelling a contract needs to be made this complicated is that the point? for people to struggle so telkom can rob them?