Unauthorised cellphone insurance debit order

I am so disappointed at Telkoms insurance policy. On February 2021 I sent an email stating that I would like to cancel my cellphone insurance as I don't need it anymore.

They sent an email on the 17th of March 20121 stating that my insurance is indeed cancelled. However I have received my statement and I see that they are going to debit again. I sent them an email they're not responding infact their service is very poor and they only want us to communicate via emails. I am so highly disappointed because I have been with them for almost 4 years now I don't deseve this treatment.