I've been tring to make the U2F-zero interact with U2F-host(https://github.com/Yubico/python-u2flib-host),but it doesn't work any more. The result is as following:
~$ u2f-register -i reg.json http://localhost:8081
Touch the U2F device you wish to register...
Unable to register with any U2F device.
Is it because the slots is full?? or else? It troubles me a lot.I would be very thankful if someone could help me out.