HTC — Desire 816g/about mobile

Address:	530002
Website:	www.htc.com/care

Hiii
This is manoj
I'm using htc mobiles from past 8 years. But i bought a htc desire 816g 16gb internal mobile. The problem with the mobile is that its process is slow and not working properly. Its getting hanging or struck. I tooked it to service centre but of no use. This is the worst model which i have used till now in htc's.
If the problem was not solved i will file a complaint that i received a duplicate piece and about the working condition of the mobile.
I need mobile replacement or my money back