DNS leak?

[killmasta93]

Hi,
I was wondering if someone could shed some light on the question i have. Currently was checking though wireshark some issue i was having with the network and, while looking though the capture i found out My DNS was leaking showing the traffic. Currently I have a windows server 2012r2 with DNS which the roots are forwarding to pfSense (unbound). and pfSense handles the DNS traffic for which i have pfBlocker. My question is what would i need to prevent my DNS to leak if i would rerun wireshark?

Thank you