Need help with firewalld


Dear scaleway community,
My machine: C2S
OS: Arch linux
kernel : 4.15.11-mainline-rev1
I wish to configure a firewall, and the firewall of my choice is: firewalld
due to my use of the cockpit panel:
which does not support any other firewall as far as I know.
whenever I turn on the firewall, the NBD disks disconnect rendering the system unresponsive.
on official scaleway website there is a tutorial on how to set up properly UFW :

can someone please instruct me how to use the scaleway tutorial, or any other way, to set up firewalld correctly so it doesn’t have any issues in baremetal servers?

Thank you so much!