I’ve had this a couple of times on different machines, Pi 4 and X86.
It’s a simple fix.
edit the file /etc/network/interfaces
# Ethernet #allow-hotplug eth0 iface eth0 inet static address 192.168.0.15 netmask 255.255.255.0 gateway 192.168.0.1 #dns-nameservers 192.168.0.25
I’ve commented out allow-hotplug eth0
Save it and run
The network was fine initially, I only had a problem once I tried to get the second network port working.