PUBG Not Authorized Error 2019 Xbox is the same problem as in years past and usually has to do with server issues. When the problem arises on PC, it's usually because of a Steam issue.
Players should check the Xbox live service if the error shows up. If Xbox Live is running smoothly, then there are a few things you can do to fix the problem.
Xbox & PS4 Players: Live server maintenance has begun and is expected to last 1 hour. A hotfix will be applied during maintenance to resolve the Radio Message activation bug, and instances of game crashing caused by weapon charms and rendering issues.— PUBG Support (@PUBG_Support) August 8, 2019
PUBG Not Authorized Error 2019 Xbox
The first thing is to check your NAT system in your settings. If it's moderate or open then you are fine. The next step is to hard reset your Xbox. Make sure not to just turn it off, but head to "Power Settings" and click "Reset."
If none of that works, you need to unplug your modem and Xbox and give it 30 seconds. These should fix the overall problem and get you connected to the PUBG server.