Bangalore Water Supply & Sewerage Board [Bwssb] — We are not using Cauvery water due to contamination and we have been charged a bill of 7890 rupees

Address: HBR Palace Apartment, Door Number SF-4, # 1-2, 1st Main Road, 1st 'A' cross, HBR layout - 560043

We are getting contaminated cauvery water in the apartment and hence, we have stopped using cauvery water since a month.
(1) However, we have been charged the default amount of 7980 rs/- and we want these charges to be reversed .
(2) Also, please rectify the cauvery water contamination

Attached are the photos and bill for reference and needful.