Circle History filters showing up from other users/profiles within Circle

Hi, I'm using Circle Basic package via the Netgear router. Been using it for about 3 weeks but not sure if I have set it up correctly.

There are 4 people in the household. I only need to restrict/control internet access for my son. I have set up the app. with profiles and set filters for him. Nobody else in the household has filtered/restrcited access and generally Circle seems to work well.  If I go to History on my son's profile I can see whatever he has visited. If I look at the Filtered section of History where I am supposed to see everything he has *attempted* to visit but Circle has stopped/blocked, in reality I appear to  be seeing URLs visited by other people on the Circle who have no filters. So e.g. I do not allow my son to visit Facebook. Within Filtered it looks as if he has visited Facebook and been blocked when I know for a fact that he has not visited Facebook at that time (I was with him or his phone was with me) but I also know that my daughter (who has unrestricted access) *has* visited Facebook at that exact time. In other words, the URLs my daughter has visited are showing up as ones my son has visited. These URLs are both been viewed on mobile (cell) phones. Daughter has iPhone, son has android. I also have android.

Have I set up the app. incorrectly or has something gone wrong ? I dont want to get 'false positives' and then have to ask my son about something he hasn't done.

Be grateful for advice and to now if anyone else has experienced same/similar.

Thanks