Open Network Bug Problem

So i've set the parental controls on the DNS, installed it on the router and it worked on all devices. But there is one problem, on the notebook, whenever someone logs into an open network and logs out of it and goes back to the main network, the parental control stops working. The same applies if next is installed on the pc together with YogaDNS, whenever someone resets the computer and turns off immediately both of them, the controls and filters stop working.