Bharat Sanchar Nigam [BSNL] — complaint regarding refusing to attend customer at 4.10pm stating time is over

Sir, i have visited cengalpattu exchange for changing my blocked sim card. I have reached the office by 4.10pm today ie (21/08/2017). I request one of the lady sitting at new sim issue counter to look after my request but that lady was busy with her some personal works after waiting for 15 minutes again i asked to attend my request but that lady refused and told me time is over so ask me to come by tomorrow, even the time is only 4.15pm. Being the working hours of bsnl is up to 5.30pm she refused to work and closed the counter and left so i kindly request to take necessary action against the person and make sure the proper working of government departments to avoid our tax payer money