Norton DNS not blocking malware sites

Hi everybody i am new here and if i am posing in a wrong section please move this topic in its proper location. I am using Noeton DNS for two days now. Today i tried to test its malware domain blocking ability. I snadboxed my browser firefox and tried  to go to some random sited listed in malware domain list. To my surprise norton DNS never blocked any sites its ways avast which blocked through its network shield. What went wrong? have i set up my norton DNS correctly? and where will i find the setting for webcontent filtering? I am not been able to filter anything right now.

 

Thanks for your time and kind suggestion

 

With regards

m_k