Fixing DNS leak in Manjaro

Firstly, check the file /etc/resolv.conf and see what's inside. Make sure it only contains the DNS servers you want it to contain. The NordVPN servers are:

nameserver 78.46.223.24
nameserver 162.242.211.137 

If there are any more, delete them, and then make the resolv.conf file immutable with the following command:

sudo chattr +i /etc/resolv.conf 

Reboot. To reverse the process:

su
chattr -i /etc/resolv.conf
nano /etc/resolv.conf 

Enter preferred DNS servers and make file immutable again:

chattr +i /etc/resolv.conf