Long story short: I made a booking for a group (6 rooms, 3 nights) about 2 months in advance for Mexico City (Hotel Diligencias). 2 days before the check in date I received a message that my booking was canceled. I did not cancel it. When I called booking.com they did not take responsibility claiming they did not cancel it either - but they agreed it was canceled. And the hotel was already sold out (very fishy business). Extremely unreliable booking agency that does not work well with the hotels and does not hold them responsible for bookings!