MTN South Africa poor service delivery

Worse customer service I've experienced ever. I signed up in April 2021 for a data sim + router. Cancelled the contract beginning of May 2021 due to poor service (Ref***) and was requested to hand in the hardware at an MTN store/agent. This was done on 14 May 2021 (*** and ER93P5). Received an email with invoice with 0.00 balance which I took as confirmation that the contract is cancelled. Only to realise but MTN still debit my account for R449. Enquiring on 10 June 2021 and was told they escalate it (Ref:***) and I should receive feedback within 3 days. Needless to say this did not happen. I then again enquire on 23 June 2021 (Ref***), this time with Acc department who told me the Manager will call me back after 3PM. Again this did not happen. After this I have spoken to several agents and was transfer from piller to post between cancellations and retention department with no success. Today 07 July I phoned again and every time they "transfer" my call to cancellation the call gets dropped. MTN is one big *****. They using the so-called automated system to hide behind to ensure they do not resolve your issues and hold on string for as long as possible and I am now going legal.