EXCESSIVE DATA - 20Gs VANISIHED IN 2 WEEKS

I purchased a Telkom LTE and 20Gs worth of pre-paid mobile data which has apparently been used up in less than 2 weeks. My only usage has been on normal websites and skype messaging. I have not downloaded videos or any large data files. My data usage on a Telkom adsl has not EVER reached this quantity in a month!<br> I have queried this at the Rosebank Telkom office on 3 separate occasions and the problem has not been addressed.<br> There is clearly an excessive disconnect between Telkom's data calculations and that amount actually used. I would like the issue addressed with immediate effect and a full refund of the data bundles already bought.