Gamertag not updating in games.

The new gamertag system is still updating and not all games currently support the new gamertags.

Information on the rollout can be found at
https://support.xbox.com/my-account/manage-gamertag-and-profile/gamertag-updates-faq

You may want to read through the gamertag update FAQ https://support.xbox.com/help/account-profile/profile/gamertag-update-faq

There is a # with gamertags that will show up in games that have been updated to work with the new change. Games that haven't updated yet won't show the #.

When I changed mine it took a day or two to fully appear everywhere.

When did you change it? I have seen it take up to a week before it shows the new tag in all places. I've had friends change their gamertag but I continued to see a mix of their old and new gamertag on different posts of theirs in my feed. The same thing
has happened when they update their gamerpic too. :/

For me, it took up to a week until the system was updated with all of the profiles of each game. If it isn't showing up for you on your xbox profile, then I suggest restarting your console by holding the power button on your console for roughly ten seconds,
then starting it back up.