Unauthorized debit on my personal account

R2632 was debited on my telkom account *** on the 23th August 2021, whereas another R1148 was debited on the 15th. I have been with telkom for more than 3yrs, now they are telling that I have subscribed for uncapped data of R1500. They took all the money for my children food and don't even know for what. Telkom, they do as they please, I was not even informed of this matter and fees to be charged.