Telkom Billing Dispute

My contract expired a year ago and ever since Telkom keeps on billing me, Numerous times I visited the Telkom shop in Kempton Park at Festival Mall. Every time(month) for the past four months I get a different agent which tells me to pay cancellation fee and it all roughly adds up to about R1200.00 and the account will be cancelled. Three months ago they confirmed that the account is on pay as u go but still I'm being billed R202.70 exactly every month. Last month I had to pay R405.00. If asked why they say its billing department and because they send the bill. So basically I'm pay for someone's stupidity or all off them not seeing the account is cancelled. I've incurred bank charges of about R380.00. I'm thinking of closing my bank account, get the Ombudsman and meet Telkom in court. I want my payments for the past four months back. Telkom agents(back office) never call you back. They let the phone ring ones and drop. I just cant get hold of the billing department. Don't ever take out a contract with Telkom! Agents can't even give answers or point you in the right direction with such queries they just pull up their shoulders and say someone will call you back.....The question is when? Maybe with the next covid outbreak?