OpenVPN Setup on D7800

Hi - I have an OpenVPN account with Surfshark and have followed both the openvpn guide on their site and another from another site to setup my connection. I can see the tun0 interface being generated and the connection being negotiated.

I then add the tun0 interface to the wan firewall zone, but cannot pass traffic from my laptop to any destination. I did try a uci command to update the DNS servers here too, but this crashed my config file and I had to restore.

Any ideas?