Did you do the Linux network settings as below:
- Linux Host Network Settings
sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A POSTROUTING -o <dn_interface> -j MASQUERADE
sudo systemctl stop ufw
Make sure your ip_forward setting with “sudo sysctl -p” and your iptables setting with “iptables-save”.
Besides, here is a similar issue: How the simulated UE provided by free5GC can ping google.com - #4 by vikash, that might help with your problem. If it doesn’t work, please provide us with your environment description, and trace files like PCAP file, Config file, log file, so that we can figure out the bug.