Bangalore Water Supply & Sewerage Board [Bwssb] — Excess water bill

Sir,
I am the owner of the house no 28-29/4, 8th Cross Maruthinagar, Madiwala, Bangalore -68.
My parents were living in this house untill 13 June 2020.Due to covid scare and since both my parents are above 80 years they have been relocated temporarily to senior citizens care cente. The house is locked since 13th June 2020 and we are not using any water supplied by Bwssb. Though we are regularly paying the minimum charges as per your bill (deducted atomatically through ECS) we have received a bill amounting Rs1235.00(Rs Twelve thousand three hundred and thirty-five)
On enquiring at the Bwss office at BTW lay out I did not get a favorable reply. I don't understand why I'm charged for what I have not used.
I request you to please look into the matter and rectify the same
Thanking you
Yours sincerely
Charlotte Lobo
[protected]@gmail.com