Boat — Boat rockerz 255/Service center is not listening to the issue

Address:

B/49 swastik society, Nikol road,diamond mill

I have boat rockerzz 250 red and left earside hasn't working so i visited to ahmedabad heenal service centre and talk about
the replacement but they are denying to do it just because, i have lost one side ear filter in the Earplug.
Just simply for that thing they
aren't allowing me to claim a complaint.
Kindly help me in this
I just bought 5 months ago.