Hello, and I apologize for the late reply.
Could you open PowerShell as an admin and run Get-AppxPackage -AllUsers -PackageTypeFilter Bundle -Name "*Microsoft.XboxGamingOverlay*" | Remove-AppxPackage -AllUsers? After that command finishes, paste start ms-windows-store://pdp/?productid=9NZKPSTSNW4P. This will uninstall Game Bar, and then the second command is to open the page to reinstall Game Bar.
Let me know if this works.