What is going on with Ranked?

Ranked queue was disabled earlier, and then the problem was fixed. I just entered the queue, got through champion select, and then got black screen when going into Loading screen, it said it can't connect to the server. I restarted client, then I couldn't even log in, it said "Unable to connect to the authentication service". And then all of a sudden I can log in, but my game is over. Also going through my profile in client it randomly disconnects with Retry button, and my internet connection is fine.