You should be able to enter around 50 games both active and inactive. Once you have archived a game if it is still going it will remain as long as the game is still going on, and then after a certain amount of time after the game ends the system will delete them.
Ok, the following screen shot shows your issue is that you have 50 active games.
https://gyazo.com/06b3e7e16905f41a5fa2d29159dff5ad
In order to join a new game you have to play some of those 50 games to clear your log so you can make more.
