Chosen Solution
When turning on the phone will not boot and the display keeps turning on and back off. Here is a video of the problem: https://youtu.be/OW-MsQnLGEM
It seems to be bootlooping. Has the screen or any other part been replaced?
Check your battery is charged up and good. There are a few things that cause Boot Looping, but one of the first things to check is a strong battery or use a DCPS to power it up . Then follow up with what lead up to this. When was the last time it booted normally, did a drop, water damage, etc… happen before it stopped. and as Carlos asked, have you replaced anything recently? opened the phone??
I am also having this problem after I replaced my screen. You just need to ket it charge to a level that the phone can operate correctly.
