A flight to Washington DC (IAD) from Brussels operated by a Brussels Airlines Airbus A330 was diverted to Reykjavik after a pilot realized the aircraft wasn’t correctly registered with the paperwork to land in the United States. The captain and first officer made the decision to turn around and head back to Brussels.
Credit for pic: https://s30121.pcdn.co/wp-content/uploads/2019/06/brussels.png
Confirmed by a few sources, the aircraft was a last-minute replacement for another aircraft that was supposed to operate the flight. The A330 was also a recent acquisition by Brussels Airlines. Each passenger aboard a disrupted flight are entitled to receive accommodation to a hotel, food, and at least $800 in United States Dollars, according to the guidelines set by the EU. The total extra costs after this error was over $1,000,000 USD. Oops.