Samsung Electronics Co. Ltd — samsung mobile service center not able to rectify the problem

I have given my galaxy note mobile for repair at samsung service centre near paradise circle, secunderabad. After paying the amount of repair they were not able to rectify the problem of discharging even on connecting with a charger. I approached them and they gave the excuse of "problem with my charger". I bought a new charger but the problem still exists and they are refusing to rectify it since one month have passed. You are requested to approach them for rectification of my problem.