That's crazy, brother, and you have the right to be very upset. It is very strange to receive a rejection without also receiving the letter. Could it be accidental? I don't know but it does happen. I strongly recommend you to order GCMS right away. You may use a third party to order the notes. The one I use and used by many on the forum is
GET GCMS - Order GCMS notes online from immigration Canada
Call them also on Monday. Yes, it is difficult to get on the queue but keep trying till you get connected and get on the queue. That's how I got to them by keep redialing.
For my first application, I too got rejection but with the letter. It was shocking as when I received the email I expected a positive update. That application was rejected for incompleteness after waiting close to 100 days. But nothing close to yours.