Xiaomi India — Phone lag and killing apps in the background

Address:

Kottayam, Kerala, 686106

I have been using a Xiaomi Redmi 2 for 8 months now.

The phone was smooth initially but since last 4 months, probably after an update it has become slow and has started killing apps in the background.
It stops wifi connection in between.
Apps like clock get stuck in between.
Music player and SoundCloud stops if some other app is opened.
Notification from news apps not coming on time.
Whatsapp needs to be opened to receive new messages.
Playstore downloads stop in between.

Are you using some hardware that degrades after sometime. I wrote to your email twice and have had no reply. Is this how you dream of becoming a top player in India? I'm dumping this thing called Mi and advising my friends against it.