incoreectly billed

Its been two months residing at the King's crossing, then suddenly last week our meter was changed and we were told it was faulty, on the 26th of June we bought the same units we bought the previous month when we moved in, now suddenly the electricity that we buy only lasts for 1 week reason being no body can provide us with a profound answer. this people need to look at their services, we cannot all have the same problem and hence nothing is being done, its not only one complex that is complaining, its very frustrating we cannot be buying electricity every week honestly. What must we do????????