Prepaid electricity meter

We started noticing from last month that the electricity units are getting finished very quickly . Our house is a 3 bedroom house and we are using gas to cook and a gas heater. Last month we spent close to R1000 for electricity when in other months less than R500 was sufficient. We bought electricity for R600 at the beginning of September and it gave us over 550 kW plus the 100 free kw so over 650 kw in total. When we tried to load it on the 01/09/2015 our units from the previous month had already finished and we had to call for the technician to come. They came on Thursday (3/09/2015) and plugged the prepaid meter by the outside meter and loaded our units. 4 days later on Sunday (6/09/2015) I checked our electricity units and was shocked to find we only had 320 units left (over half our units disappeared within 4 days). We went to the electricity department on Monday and were told to pay for a meter test which we did. No one has come and today I woke up in the dark all this after spending R800 on electricity since 01/09/2015. How do lights, TV and a fridge and sometimes a geyser consume so much electricity??? EMM PLEASE COME AND REMOVE YOUR FAULTY METER TODAY!!!!!