The worst mobile company is Telkom mobile

I had a Data sim only contract with Telkom and I used to pay just over R100 for 10 Gigs this was between the period of 2017 till 2019. Out of the blue large amounts ranging from R600 to R2300 and R3000 were debited from my FNB account. Till date I've not been able to have a solution and an explanation for this. Telkom mobile is the worst.