@caidao 

As said above, if you child is using a vpn the parental controls won't work,  

My boy was doing the same he would activate it before his cut off time and it would allow him to stay online all the time and access blocked websites including adult sites ect.  

I have literally had to add all of his devices twice for wired and wireless so he eventually couldn't get online when he shouldn't. 

I had to add on the website blocker list vpn dot com as a broad website domain coverage so he couldn't log onto one of those websites to access any vpns. 

That seemed to nip it in the bud until this latest release of tether and ax72 firmware  update now I can't even reset the parental controls as the update has wiped the previous restrictions and won't let me save them again, if I try and save the new settings more than 3 times it crashes my whole network. 

I even pay for the upgraded homesield stuff and it's not working. 

Failing that I'm now having to take away things from his devices and his mobile so he has to actually go to sleep instead of not being trustworthy enough not to be up past bed time