My 3ds can only read games after I close applications

Let's say I have a game in my 3ds and I turn it on, it can read and launch the game with no issue. But if I turn on my 3ds and the game's in it and I want to change games, I'll take out the current one and put in game 2. My 3ds will not be able to read game 2. If I launch an application like system settings for example, then close out and go back to home with game 2 still inside, it will read and launch it no problem.

I have no idea what's going on. I can't see any bent pins when I shine a light through it.