Intermittent detection of USB 2.0 keyboard thru Anker hub on macOS Catalina
I have the same issue. My USBC hub is Deltaco USBC 1266.

You probably don't need to reboot, just move the keyboard from one slot to another or move the whole dongle from one port to another. This usually resolves it for me.

I had this problem when the computer was new in 2016. Whatever the OS was then. And I got it again after upgrading to Catalina.