Telkom Bad service

Hi, have a contract with Telkom for WiFi? Anybody experiencing loss of data.... for no reason We have secured our rooter so that no one can hack it, but still loss of data? Even when rooter is plugged out! And we are on vacation far from home..... still data is loss and being used by someone else other than we that are paying for the account. Anyone else experience the same problem? Have made a complaint last month, Telkom just says... data is used. Called the call center, data is used and we don’t have any data left for December!!!!! Never had this problem, have been a year with Telkom, last two months experience bad service froM their side. Can anyone help me, who must I call, can I put a stop order on my account for paying for data that I don’t use !