HTC India — htc desire 830 dual sim

I bought this phone for 18k in december 2016 and found this useless to me. I has lot of problems. I visted 5 times to service centre and still all problem persists. Every one or 2 month i have to factory reset this phone so everytime i have to carry pen drive to backup my phone data. Sometimes it switches off automatically while using even while talking, and regulary while caputring video. Even with 3 gb ram this phone lags. Camera autofous never works and sevice center told me that camera is damaged and asks for 5k to replace it. It heats a lot. Too plobems in this creepy phone. Now i will never buy htc phone and i will prevent my family members and friend circle from buying htc product since htc sells useless products.