My phone keeps shutting off??? PLEASE HELP!?

[Jasmine]

I have a samsung captivate glide phone. It does this thing, it shuts off by itself, and turns back on by itself. I'm losing followers on instagram because i can't post. I can't even screenshot anything. I've tried almost everything that people have said, but it doesn't work. please help ):
And i've tried putting a new battery in. but it didn't work. it kept shutting off??

[Nrml]

Your battery needs replacement or visit near cellphone service center.

[RØBÊRT]

I am also dealing with the same situation but the little bit of difference is that my phone (samsung galaxy y) hangs itself and then it switches off and itself on.
If your problem is just the same then you cannot do nothing........
I am also annoyed with this.... But nothing can be done.... All i do is i keep on force stop my running applictions,clear ram,and since my phone is android i have also installed clean master.........
Hope this helped.....