Why is my lg g2 rebooting when i sleep the screen?

[AC Question]

Not happening all the time, but just started yesterday. If I sleep the screen the phone shuts down and tried to restart. It gets stuck on the lg screen. I have to manually power it down and wait a few minutes before starting it again. No new apps, only thing I did was change the lock screen password. Tried putting it back to what it was and still doing it.