Dell HE monitor hubs may have important LAN update issues out of the box.
The Dell Canada site provides a DELL-LAN-FIX update, or updates can be installed using Dell Command Update from the company portal or Dell Support Assist.
If the USB-C connector doesn't work (i.e. no LAN), use a USB-A Ethernet adapter to connect to an available Ethernet wall port. This will let you install and run Dell Command Update to apply the necessary Ethernet LAN driver updates.
After the installation, the Ethernet USB adapter can be removed and a reboot will restore the LAN ethernet connection.