Xbox Windows App needs to have option to fully sign out - it's a child safety issue

Windows allows fast user switching.

Create a separate account on your PC for your child (since you have made a child account already, he can simply sign in on Windows 10 with that account).

Then secure your computer account with a password your kid doesn't know.

Whenever you're not around, make sure you are not actively signed in on the PC (simply press Windowskey + L), and the kid is able to sign in with their own account then.

That gives them their own desktop space, and they can't use your Xbox app.

It would have been a child safety issue if the child account could have full control. You as a parent have the duty to look after your account and your child's safety

To post suggestions on opinion in bettering the service:
https://xbox.uservoice.com

Hey there MrBaz007!

Thanks for reaching out to us. To make sure, does your account have the current

permissions in order to play online?

Also, let's try signing out of the Xbox App, restart your Windows 10 device then sign back in.

Be sure to double check that your Xbox App is fully
updated as well!

Hi again Elixir,

You can try changing it from the internet. Here how:

Change your child’s Xbox privacy and online safety settings
Applies to: Xbox OneMicrosoft account

Only a parent using the Microsoft family group feature can change Xbox privacy and online safety settings for a child account. If you're having trouble changing your child's settings, make sure your Microsoft account is a parent account in a family group.
See whether you're listed as a child or an adult in a family group by signing in at account.microsoft.com/family. To change your child's settings:

• Sign in to the Xbox settings page with the parent’s Microsoft account. You may be asked to verify that you're the account owner. If you're having issues
  signing in to a Microsoft account, go to Microsoft account help.
• Choose the gamertag for your child's account. If you want to update the privacy and online safety settings for the parent or adult account, choose that gamertag instead.
• Select the Xbox One/Windows 10 Online Safety tab or the Privacy tab,
  review the settings currently in place, and then update those you want to change.
• Select Save before leaving or switching to another tab. If you don't save the changes before you move to the other tab, your changes won't be saved.
• Have your child sign in and sign out of their account to make the changes take effect.

Learn how to block inappropriate apps, games, and media

I have reached out to discord already on the advice of Microsoft support. Discord indicated it was an issue with the family safety settings for the child account and that I needed to enable 3rd party apps.