It is not an officially supported platform. I remember another report on this forum, but I could not find it now. Possibly because the issue was shared on a screenshot or I just searched badly. .
You can check the engine logs to figure out why the network was not created.
journalctl -e -u docker
I think last time the problem was with some kernel modules for nftables. I’m not sure. But it is possible I just remember this issue on Debian 13
where the error message as
What was the expectation? Why should that variable exist?