blue screen

I recently got an iPhone 6 and a few weeks ago it continued to work but the charging port wouldn't work. I waited for it to die completely and then when I charged it again it starts to turn on, then the screen switches back and forth from the white screen with an Apple logo on it to a completely blue screen. It does this until either it dies again or I force restart it. I switched to an old iPhone for 2 weeks to see if the issue would work itself out, but it still hasn't.