I was having trouble with this issue and had tried everything that everyone had posted with no success. I finally was able to contact Google and got someone on the phone. With their help I had it fixed in minutes. Here's what worked for me...
It worked for me. Hope this helps someone. Also, be aware they did say that it could take a few minutes for it to work -- possibly up to 30 minutes after restarting the phone. I did notice when restarting the phone that the Google Play Store had to update itself first. But now it is resolved. Finally!