Change my son's setting for Xbox - how to log out and log in in Android

Hi, I'm trying to change my son's Xbox settings so he can play Minecraft on my Android phone on server with a friend. When I went to to the xbox page to change the settings, it says: "Parents if you update your
child's settings, they will need to log out and log in for them to take effect." He does not log in and out into my Android phone, although I do enter a PIN to let him use my phone. I do remember when I first set up Minecraft on the phone, I had to go through
the process of setting up the Microsoft family account etc including him. I'm wondering how you log out and log him back in on Android when I cannot access that kind of page on the phone? Please let me know. Thank you.

:)