self-assigned IP Issue with LAN

I have a new Macbook M1. At first the Ethernet was working fine, but now it will not connect. The specific error says "USB 10/100/1000 LAN has a self-assigned IP address and will not be able to connect to the Internet."

My wireless is fine, this is just the ethernet (I am using a docking device).

I have tried quite a few steps to fix this, all of them detailed here: https://www.igeeksblog.com/internet-not-working-due-to-self-assigned-ip-address-on-mac/

Deleting files, creating a new connection, resetting the network settings, restarting, adding DNS addresses. Nothing is working. Any suggestions?