Additional Water Charges for UnOccupied Flat

Dear Team, I am living in bangalore in apartment and this is registered association. I have paid all maintenance charges. My flat was un occupied for 2 years and all maintenance charges were paid for this duration.Since water was getting from borewell so there was no additional charges applied in maintenance.Our society become dependent on water tanker for water and additional water charges were posted for all flat even for my flat as well.I had marked my flat as not occupied in one of our app that we use.For few of months I have received waiveoff on additional water charges as my flat was locked and water connection was closed. I have issue with two months additional tanker water charges which is not getting waive off by association.this is not big amount but I feel this should be waived off too.maintenance charges and this tanker charges appears separate on bill where maintenance charges is collected as quarterly and water tanker charges collected separately on monthly basis. I am looking for legal advice on this.As association will be implementing water meter and this issue will get resolved in future on no water no charges but same is case now as well I have note received water and that is reason I don't want to pay additional tanker water charges. Please provide your suggestion. Thanks