Captive Portal

Please can someone help me?

I cant understand why i cand get work fine my captive portal monowall setup.

lan 192.168.1.1 / 24 dhcp 192.168.1.100-->192.168.1.254
dmz 192.168.2.1 / 24 dhcp 192.168.2.10-->192.168.2.254

Rules are:
DMZ
Proto   Source   Port   Destination   Port   Description   
       *    DMZ net    *    *    *    DMZ NAT


LAN
Proto   Source   Port   Destination   Port   Description   
       *    *    *    *    *    Default LAN -> any


Clients get connect and i can see captive portal but after 30 minutes the system doesnt work.
I cant see the CP page.

Can the problem be the rules of monowall firewall??

Please help me its 4 month i try to understand whats appening

If you need more info tell me what you need

Thanks