Does your Google account have Two Factor Authentication? Someone on xda had a problem because of this and they created a new Google account and it worked fine following the directions in a link in this thread here:
https://forum.xda-developers.com/hd8...-hd-8-t3855811
You can also just side load the apks for whatever apps you want. Some paid apps including Moon+ Reader Pro don't check with the Play Store.