Battery has recently been replaced. When you have greater than about 50% battery you can power it up. At less than that you have to plug it into the Droid charger.
I was thinking it was my problem. Then I went to the web and noticed it was happening with the new Samsung S8 plus and lots of other
phones on 7.0.
Ain't that a kicker, upgrade to the new S8 plus (at premium $$$) and have the same problem..... ooops same Android software.