Norton family not working on on my kids devices

i have downloaded Norton family on both my kid's hudls about a week ago. they both show as been protected but when i look to see their usage, it tells me there has been none. my eldest was on it all day last wednesday, supposedly doing research for her school homework, i know she uses Facebook on her mobile, but need to block it on the broadband as she has caused problems on it for herself before due to inappropriate messages. i have tried to block it through my router settings but dont know if thats working either.