Sys-vpn-firewall has no network until I reboot it

I set up my system with the usual recommended set up:

sys-net <> sys-firewall <> sys-vpn <> sys-vpn-firewall

The problem is that when my VPN connects automatically, sys-vpn-firewall has no Internet until I open its terminal, run sudo poweroff, ans start it again.

How can I troubleshoot this problem and fix it?

Did you configure anything special in sys-vpn-firewall?

sys-vpn-firewall uses a disposable Debian template (actually Kicksecure 17, that I use everywhere else in my system).

This is still happening. But I realized that I do have network. What I don’t have is DNS.

curl http://1.1.1.1 perfectly works.