Telkom Data Plan Disaster!!!

I signed a 24 month plan for 20gigs and everything was fine first month then suddenly my data would be over in 2days. When I requested my data usage details I was told they can't give me and my usage was not capped as requested and was being overcharged. Made multiple calls and requests for my records to no avail until I stopped paying and now I am being harassed by their debt collectors though my queries have been ignored.