Hello everyone
I had exactly the same experience as you, ccomtec2009. Initially I searched for the LAN adapter in the Macbook settings under "Network", but nothing was there. After half a day I looked again and saw a new adapter "AX88179B", which is the Icy Box LAN adapter. I can now work without WLAN.

When the Icy Box is connected to the notebook for the first time, it is important that this notebook is already connected to the Internet via WLAN with the router or a hotspot.
Windows can only download and install the necessary drivers for the Icy Box via an active Internet connection.
As soon as the Icy Box drivers are installed, all connections will also work.

We have several in operation, also with LAN cable. All of them work perfectly. Have you ever tried them on different laptops? Is the USB-C socket defective? Or else, of course, the Icy Box could be defective.

Mine works perfectly, 𝗺𝗶𝘁 LAN cable, just plug it in well so that it makes contact (possibly test with different cables...).