Sky rocketed water bill

Good day .. I stay in one of the Afcho buildings in Midrand ( minuet) and I logged a complaint in March where by my water bill sky rocketed from R90 in January and feb to R600 .. I logged a complaint with them in March and didn’t received a response even though I have been calling.. I called them on Friday the lady said she will follow it up the next thing at 4pm I get an sms to say I am liable .. there were no leaks and I owe that ammount .. spoke to other residents and they don’t pay that ammount maximum they pay is on average is R160 .. when did they in the 2 hours investigate to confirm that we owe that much ? I am not getting any joy and I don’t know what my way forward is but I’m fed up !