According to a report from Dave Meltzer in the Wrestling Observer Newsletter, Ember Moon has suffered an injury and may be out for up to a year:
Ember Moon will be out of action for a decent length of time with either an ankle or an Achilles injury. The latter is really nasty, as that can be close to a year. Ankle wouldn’t be nearly as bad.
Ember Moon was in flux following a loss to Bayley at SummerSlam. We wish her a speedy recovery!