Asus — Asus zenfone 2 having problem

Address: Guna, Madhya Pradesh, 473111

Bought my asus zenphone 2 4gb ram in december 2015 online. But from last two weeks phone is not working properly. When ever anybody calls, sometimes the phone screen gets hanged and i m unable to receive the call. Similarly some times after attending the call, when i want to cut the call, the screen gets hanged, resulting in unabling to cut the call. Thirdly, the sometimes while opening the lockscreen, remains hanged for several minutes. I am currently facing a lot of trouble as phone not working properly. Kindly solve the problem by replacing the piece and maintaining your esteemed image to customer.