The best way to fix this problem is to uninstall both apps then install a fresh version from the Google Play Store. Uninstall then reinstall both the Poweramp and Poweramp Full Version Unlocker app
POWERAMP FULL VERSION UNLOCKER APK NOT WORKING FOR FREE
You can download the trial version for free over at the Google Play Store which should allow you to use the app for 15 days after which you just need to play US$5 to keep on using it.
Poweramp is one of the best offline music players that you can use on your Android phone. To fix this you need to uninstall the Poweramp app and the Poweramp Full Version Unlocker app then install a fresh version from the Google Play Store. The Poweramp failed to verify license error that occurs on your Android phone is caused by the app unable to verify your purchase. Download Poweramp full version unlocker for free- 100 works- No root or jailbreakWhile your phones stock music player is probably a totally serviceable app.