Samsung Mobile — Useless service center

Address:	New Delhi, Delhi, 110092
Website:	www.samsung.com/in/support/erms1?isVoc=true

I have submitted my phone first time in head office and seccond time at nearest service center both time my phone has display problem but at first time they damage my crome and didnt accept that and second time they change my phone from 4G to 3G . when i went to them they said u changed the back cover which contain logo of 4G the senior person Mr Ravi was there he said you had changed your cover because Galaxy S5 doesnt have 4G model. However When i have submitted my handset second time they took took thirteen days while saying that we are waiting for part to change but my warranty is ending on 11th Nov 15 and submitted my handset on 3rd Nov 15. And when i get my handset back they said we have repair same part and we didnt change any part . What the hell and now my vibration senstivity Who gona lsiten to it ...