Telkom am disappointed

Am very disappointed with telkom.I have a contract with them for R139.October they debited R356 which is 3 times the amount am paying I went to their offices to complain then I was told to request a call then few minutes later one of their consultants called and told me that they debited that amount because of the subscriptions on one of the phones that are connected to my router my question is why do they allow such to be charged on my account without my consent since our contract is for R139 if I need more data I call them and confirm my personal details before they top up but why these subscriptions they are allowed without my consent.I was then told that the subscription were cancelled now yesterday when I woke up I broke into tears when I saw that they debited R424 which is 3 times the amount again Am very disappointed with telkom really last month had to ask for money from friends for transport to work since they took my money that I budgeted for transport now they are doing the same thing This is unfair