[CLIENT] ARAM Game automatically declined when pressed Accept button, now prohibited to join queue

Pressing the Accept button leads to an akward behaviour of the client. It seems, there are connection or communication errors.

1.) Just after I installed the recent patch, I experienced trouble when entering a queue for ARAM. At first, the client waited over 10 seconds after I pressed the Accept button (at about 30% full bar), then ended the queue saying I had declined. Which I have not.

2.) Next, I had several tries until I managed to play two games normally.

3.) After that I tried to enter a game again, someone dodged champ select. Next time, I experienced the above behaviour again: pressing the Accept button led to an unusual waiting time after which I was thrown out of and banned from the queue for 15 minutes.

My internet worked fine the whole time. My router doesn't show any unusual log entries, and I didn't have problems whatsoever.