Had this all working perfectly and then moved my install to a new host. When connecting to the guest wifi, captive portal kicks in, login and then I get 'access denied: authentication configuration missing'. Looking in the captive portal logs there is nothing there and when I check the firewall logs from the device they're all green. It has also added the session as active to the captive portal.
If I reconnect the device it'll go straight through as the captive portal already has an active session. Any ideas as to what I'm missing?