Try resetting it. There is a pin hole on the commander core. It's the same process as the pro with the steps below. I have had this happen before to me and was able to reset it and reappear in the software.
https://help.corsair.com/hc/en-us/articles/360057712532-How-to-Perform-a-factory-reset-on-the-Commander-Pro#:~:text=Locate the reset button inside,then plug it back in.