Ensure that you are Disconnect from the VPN
Select the three horizontal dots to view All Settings
Additionally you can press the down arrow at the bottom of the menu and scroll down to Quick setting box and select the three horizontal dots there.
Within the settings window go to the Network Connections tab
Within this page you will see a drop-down menu under Name Servers. By Default, the PIA Client is auto connected to PIA’s DNS Servers. You can choose to use your existing DNS Settings or to Set Custom DNS settings from within this menu.
Please be aware that using your Existing or custom DNS Settings may expose your DNS traffic to third party.