It sounds like the Captive Portal service isn't binding correctly to the WireGuard interface. First, verify that the interface `wg0` is assigned under *Interfaces > Assignments* and enabled. Then, in *Services > Captive Portal*, confirm the zone explicitly includes `wg0` and that its IP (10.20.0.1) matches your WireGuard subnet. Restart both the Captive Portal and `lighttpd` services. Also, check `/var/log/system.log` for startup errors — missing `/var/etc/captiveportal` usually indicates the portal never initialized. Re-saving the zone often regenerates this directory and fixes binding issues.
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