OK, so the plugin is listening on this port and there’s not local linux firewall, but you still cannot connect to the port from the outside, which is strange.
Could it be that there is another IP address active on the system? Maybe even a public one? Your output looks different from mine (mine has the * character which means “listen on all interfaces”, yours shows the IP addresses one by one as if you had configured it to do so).
Can you maybe also share the full calls plugin configuration?
mmctl --local config get PluginSettings.Plugins.com.mattermost.calls
I’m still thinking that the Azure Firewall is to blame, but I’m not sure.