Why does IPhone 4 flashes on and off?

My Iphone all of a sudden wouldn't turn back on. When I put it on charge it flashes the apple logo. I tried holding the power and home buttons still nothing. I kept it on charge and the phone went back to the home screen I put it on factory reset and reseted the phone. When I take it off charge it turns off. Need Help.

My iPhone 4 is like that too:/ Maybe there's a problem or something

Contact apple

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