eThekwini Metropolitan Municipality - Arrears in metro bill

I am a pensioner and live with my wife, we both collect a state grant, recently i received my metro bill with an amount of R96714,68 in arrears. I have paid my bill every single month without fail and then a guy from the municipality came to my home and changed my meter to a credit one. After my meter was changed i received my bill stating i have the above amount which is in arrears. I have never not paid my bill, I have never been dis-connected by the municipality at all, where did this amount derive from. I don't have this kind of money to pay nor will have this amount even if i made an arrangement. This bill is not mine, i have been to the rent office and complained numerous of times and i have been told that the meter was tampered with, all of a sudden in a month this has happened, we have never tampered with the meter nor have we not paid and been in arrears. I would like my bill to be checked