Bogus billing by impact meters

Kindly assist ,I've been paying an average of R 459 per month for the whole year 2025 just once I billed R880 which I never followed up about the excessive charge till now having received a bill of R 1680 having leaving in a one bedroom apartment with only a shower.i the sent an email seeking explanation as to what led to this bloated bill. Understanding very well that the R 400 is fortheprevious month then the bill or R 1200 is I formed by what.im yet to get a response from this people to clarify me on this bill