As noted, King Barrett has not appeared on WWE television as of late is because he is dealing with a nerve injury in his neck. Barrett is still traveling with the WWE talents to all of WWE events, but cannot work so he is not used.
Barrett tweeted out the following:
Rehabbing a little nerve damage in my neck at the moment, hence the disappearing act. Nothing major, but not worth taking unnecessary risks.
— Stu Bennett (@StuBennett) December 15, 2015
He is not expected to be out of action for too long.