Bangalore Water Supply & Sewerage Board [Bwssb] — RWH payment refund

Our house was constructed in 2008 and is not liable for rain water installation as the RWH was Introduced only in 2011 but I have been receiving bill from BWSSB for RWH regularly and have paid for the same. I have submitted a letter for refund of the paid amount for RWH till date and has not yet been Refunded. My RR number is N-221934
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