Logs show client attempts, but it does not fully connect
There might be many things, but the most frequent is a firewall. If You run node via docker image, check that ip_forwarding is enabled on a host and that UDP service port is allowed from outside.
check ip_forward status:
cat /proc/sys/net/ipv4/ip_forward
enable ip_forward if disabled:
sysctl -w net.ipv4.ip_forward=1
It also might be that the default firewall forward and input policy is set to DROP. In that case, try setting it to ACCEPT. Generic way to do it, provided there are no other interfering rules:
iptables -P FORWARD ACCEPT
iptables -P INPUT ACCEPT