continuing from my previous post....
I just read help text that say license is only checked once, unless the app is re-installed, or a ROM update occurred.
For this second fail, There was maintenance security release update about a week ago, while it kept the same Android release 6.0 level, I'm guessing that qualifies as a ROM update? I guess that must be what triggered the recent license fail. Currently Poweramp say's Purchase Verified Store:Play under settings-about. So this license problem should not re-occur, right?
I don't remember the details of the first fail, it did happen when the phone what fairly new, so maybe the app timed out trying to confirm the license. I most always use the Poweramp where there is no wifi, and I keep my cell data turned off which must aggravate this license issue..