EXPLOITATION OF EX-TELKOM CUSTOMERS!!!! DISGUSTING BEHAVIOUR FROM TELKOM!!!

My husband and I have been trying to cancel our terrible Telkom service since last December 2019. We've called in to call centers countless times because for some reason you cannot cancel your Telkom service by going into a Telkom store and speaking to someone face to face. I thought for one brief moment last year October 2020 that I was successful when I emailed the Senior retentions officer to communicate the disgusting service of Telkom and was emailed back to confirm that our service has at last been cancelled. Then January this year (2021) I received an email with an invoice attached stating that we owe Telkom money for our cancelled service. And then this month, February 2021 another invoice received with an amount owing by us. I am so sick and tired of businesses like Telkom taking advantage of the average worker. Can anyone give me advise on how to take this matter further? Who can I contact personally and not a call center number please.