2 WAN 5G Router connected with Palo alto Firewall

I m using the 2 WAN 5G Router connected to WAN Port and the 2 LAN ports are connected to Active Passive Firewall with 192.168.100.100/24 interface 5.
I have assigned in untagged VLAN DHCP same in 192.168.100.1/24.
when I m connect the laptop getting IP 192.168.100.11 and works fine when I m changing the same LAN and connected to Firewall 192.168.100.100/24 interface 5 it’s not work
Please help