Hi,
Try this:
In System -> Settings - General configure DNS servers (example 8.8.8.8, 8.8.4.4) and unchek "Allow DNS server list to be overridden by DHCP/PPP on WAN"
Enable DNS Resolver instead of DNS forwarder
At DCHP configuration of GUESTWIFI interface, leave DNS servers and gateway blank
Be sure that hostname is blank in captive portal zone definition
Try this:
In System -> Settings - General configure DNS servers (example 8.8.8.8, 8.8.4.4) and unchek "Allow DNS server list to be overridden by DHCP/PPP on WAN"
Enable DNS Resolver instead of DNS forwarder
At DCHP configuration of GUESTWIFI interface, leave DNS servers and gateway blank
Be sure that hostname is blank in captive portal zone definition