So every time I keep queuing for a game with my friend who is a lvl 8 and im lvl 10 it takes more than the approx time but we are never able to get into a game. We have tried inviting each other and it still doesn't work. About last week it was working perfect with no issue when we invited each other. But it works fine when we play alone. Can you guys please help and tell me what we can do so we can run games together? Thank you so much. And both games were installed correctly.

What mode? Is it normal draft, or normal blind pick? Dominion, Twisted Treeline, or Summoner's Rift?

There are six possible combinations, and a lot of them are extremely unpopular for people of your level, particularly any draft mode. Chances are the matchmaking system is having trouble finding 8 other people around your level who also want to do the same thing (or even qualify, in some cases), and also have the patience to sit in queue.

SR Blind Pick should get you a match consistently fast.