Others on this board will probably have a more complete answer, but here is what my experience with this is.
Sometimes phrags, for whatever reason, have a deformed bloom. The next bloom, next blooming cycle -not on the same spike, should be fine. We have had several do this. Usually it is the first bloom on the plant, but we have had the second bloom cycle start or end with a deformed bloom.
Just keep growing the plant. The next bloom should be fine.