Horrible service, need to cancel my contract.. Been trying since October 2019

I have been trying to cancel a contract since October 2019! I have followed all the online steps and spoken to the retentions department however I am still being debited.. I have called several times and sent emails and still I am being debited... Each time I call it takes forever to get through to someone and then the agents either cannot call me back or when they do they put me on hold while their systems load and then hang up on me... I have returned debits twice now and each month telkom changes the debit date and just debits my account on a different date... I am so sick of dealing with this **** company honestly.. All I want is to cancel my contract