ESKOM *****ing kWh and poor service!

After 3 years of calling and emailing, Eskom still cant provide me with the service i requested. Let me explain, since i moved into the present house, my bill is very high (the 1st month was estimated on R9,000 - 5707kWh for 22 days!!!). The next month was actual, so the bill came down to R3,400 - 2412kWh for 53 days! The month after that they estimated 1495kWh for 31 days and continued similarly until now. In 2016, after re-looking at my consumption and calculating the load, i realised that i have not spent that much electricity so i decided to purchase and install Efergy monitoring system with 5 current sensors, one was for the whole house! After only few months it showed that the difference between my readings and Eskom readings differ a lot! To compare, 19th November 2017 up to 20 Jan 2018, Eskom says i spent 1588kWh and my Efergy says i spent 1320kWh!!! I know there might be a difference of about 2-5% but it cant be 20%! 268kWh on the price of R1.7961 is R481 excl of VAT and i have been in this house for almost 4 years! Over 4 years that is over R13000! I have tried so many times to get Eskom to call me when they do the reading, logged many complaints and only response i received was a photo of "some meter" which i cant even say who's is it! I am sending the last email complaint and if they don't want to show me the reading, i will take the legal action. I am sure someone will respond to a letter from the attorney! It makes me think that someone is "tapping" of my meter or meter is faulty and they are not interested in finding that out as it might get them to pay back large amount of money!