Last week, Alexa Bliss was revealed as the captain for Team Raw at Survivor Series albeit in a non-wrestling capacity. Bliss hasn't competed in a WWE ring for the past few weeks due to a concussion and was even pulled from the WWE Evolution pay-per-view, and there isn't a specific timeline for her return.
During the most recent edition of Wrestling Observer Radio, Dave Meltzer provided more details regarding Alexa's injury. Meltzer revealed that Bliss had suffered multiple concussions in a short period of time, which is why WWE hasn't cleared her to compete in the ring just yet. Dave noted that WWE is very cautious with Bliss, and it remains to be seen when she would be cleared to return to in-ring competition.
Bliss was originally scheduled to face Trish Stratus at WWE Evolution, but was pulled from the event after reportedly suffering a concussion just days before the show.