Problem with node device authentication

During testing with the knot device, I found a problem with the thing-token authentication. The knot is confirming the device authentication message without re-verifying the thing token. My test:
My device sends the registration message and receives the confirmation along with a think token, then an authentication request is sent to the knot without informing the thing token, and the confirmation is received without errors. In the image the babeltower receives an authentication message without any token and confirms normally.