Municipal Corporation Of Delhi — they are not taking coin of 1 rupee and say it is not valid now a days

Address:

Mayur vihar 1 tool booth

I have only 100 rupee cash and in this i have 5 small 1 rupee coin and say it is not valid coin and argued a lot with me and say stand here and give this coin to other people if they take then we take and its happen at mayur vihar-1 mcd tax when i m coming from noida towards akshardham is there any proof that small 1 rupee coin is illegal as i know as per rbi small 1 rupee is also valid