Xbox Pause/Blocking is not working

My son's xbox automatically creates a new Xbox name.  I have tried pausing over 20 xbox device names.  When I go into the room the device continues. 

1)  I have reset my internet.  Did not work

2)  I have changed my passcode (caused me to reset all my devices).  Did not work.  (and he does not know the passcode).

3)  I have manually paused the Xbox with the green dot.  The xbox continues on my main internet.  I know because I have asked him to show me which network the Xbox shows its operating under. 

Please help so that I could create  xbox pause limits.

Thank you