Serial over USB not responding after a while

[FinnHoller]

I am sending repeated "scan" commands to my TinySA over the USB interface. It works fine for a variable amount of time, but afterwards the serial endpoint just stops respondig. The TinySA itself works fine, but it is not responding to serial commands.

The red light next to the USB-C port also turned on after unplugging and re-plugging the wire once the tinySA got unresponsive.