My phone goes into a sleep-like mode which requires me to reinstall the battery to get it back on

[AC Question]

The blue light on my Note Edge 4 is flashing, but I can't get the screen to turn back on without reinstalling the battery.
It also randomly restarts. I bought a new battery and did a factory reset, but it didn't fix the issue. I also put it in safe mode and it seemed to help, but then by the end of the day, it was doing it again. I have not dropped the phone or damaged it in any way. Please help! Thank you!