The entries you are seeing with the sip debug are the result of a bug in EPM that only shows itself when using PJSIP (they will not be related to any registration issues).
https://issues.freepbx.org/browse/FREEPBX-14218
Some of the Phone Apps need to update the LEDs on the line keys. Some do not. EPM is incorrectly assigning a hint to the Phone Apps that don't have/need LED updates that you have assigned to your phone. Asterisk knows nothing about those hints and is letting you know. This error doesn't seem to exist in CHAN_SIP and so doesn't appear if you aren't using PJSIP even though the issue still exists. I have been told that those errors can be safely ignored.
Note that this issue may take some time to fix as the team have deemed this to be an Improvement rather than a Bug. It seems to be clearly a bug to me so I'm not sure how they came to that conclusion.