Lenovo — Lenovo vibe K5 Note Not working proper

Address:

382418

I bought new Lenovo Vibe K5 Note phone from Flipkart on 24th March 2017.
But i faced the problems in Mobile since 2 or 3 days after start using it.
The problems are like Phone Goes hang anytime and doesn't start.
Application goes stop anytime.
And many problems face like it doesn't have Galary to see photos and Videos and also don't have note to write.
so help me to know that what to do next to use this phone without troubles.