If you're having trouble finding matches and want to find someone to play with, you should probably check the Killer Instinct Discord. It's always active, and there are always people looking for games. KI's REALLY not as dead as you think. It even has a beginner lfg chat, so you don't have to get bodied by a killer every time you go looking, either. And it has a lot of resources for learning, and character discussion.

Killer Instinct Discord[discord.gg]