iphone 6 plus does not turn on

[iMore Question]

was flat battery , put on charger , doesnot turn on , apple logo screen appear when use combination of buttons

 

[Rob Phillips]

Welcome to iMore! Have you tried a different charger. I had a colleague reporting the same issues yesterday morning (he blamed his iPhone for not getting to work on time). I had him use a different charger and it worked just fine.
It could also be your battery. Apple's iPhone batteries are designed to retain 80% of their original capacity for 500 full charge cycles. After that you're on borrowed time.