prepaid electricity charges

IHS is deducting money from our electricity at south gate ridge we get almost half of the unit that we pay for for instance when you buy R100 electricity you are suppose to get 69 units we only get 39.4units they gave me the number to call nett vendor which supply them with electricity they confirm that the body cooperate ask the to charge the price they are charging us. when i spoke to the gentleman from net vendor he said he will send me the documentation through to show how much we are charge for the units as per the BC. he never send it through when i queried it again he said he cant send me the documents through as the body cooperate needs to ask for them. phone the property manager again he was going to ask never happened. so to me it that ihs property management is taking almost 40percent of every purchase that we make for themselves. and nobody can give you any clarity.and this is n prepaid account