Called Market Surveillance, Complaints and Inquiries they said under UMIR 10.9D (Universal Market Integrity Rule) the trade was re-adjusted. There was an issue with the trading, could have been a number of things that caused it.
When they see unusual trading, they can vary or cancel a trade which in the opinion of Market Integrity Official is deemed unreasonable.
It doesn't happen often.
I was told the reason for the drop is not made public.
Register for free to join our community of investors and share your ideas. You will also get access to streaming quotes, interactive charts, trades, portfolio, live options flow and more tools.