Cannot get my shards

For the Executrix event, it says it's locked to people who have a 7 star Executrix.  However, my executrix is 6 stars with 70/100 shards.  I need 30 more to get to 7 stars.  Which I would have gotten 15 yesterday, and the other 15 today to get there.  However, it won't let me play because it says it's already 7 stars.  There are no other methods to get it to 7 stars either.

Is there some help I can get with this?