DHCP would work regardless, so Im positive ts not license issue. As Phoneboy said, please confirm packets even get to CP itself.
Say src ip is 1.1.1.1 and dst is 2.2.2.2
You can try something like below:
tcpdump -enni any host 1.1.1.1
tcpdump -enni any host 2.2.2.2
fw monitor -F "1.1.1.1,0,2.2.2.2,67,0" -F "2.2.2.2,0,1.1.1.1,67,0"
You follow srcip,srcport,dstip,dstport,protocol
You can also use below site my colleague has made over the years to help people with different captures, hope it helps
https://www.tcpdump101.com
Kind regards,
Andy