BWSSB — BWSSB Water Bill erratic reading and bill amount

Address: Bangalore, Karnataka

we got water bill of rs 13, 000 for not using it for nearly 6 months one person from BWSSB came and told me we need to change the meter but then also this month i got water bill of 17, 000 i have only one tenant and only 2 people living there for more than 6 months but i do'nt know how i am getting high bill value others are getting a mere100 rs for a month my rr number is RR number E-333396 no 11 vinayaka layout rama murthy nagar bangalor - 16 please any one to help me