Did you do the troubleshooting bits from here?
https://learn.pimoroni.com/tutorial/sandyj/setting-up-the-keybow-os
If you had plugged into the wrong USB Jack on the Pi it wouldn’t have been detected. It needs to be connected via the data port, just for the record. Not the power port.
It sounds like an OS issue? Maybe a corrupted download? Just for the record, I don’t own a keybow. I have tinkered with gadget mode though, its been a while since I did that though.