Happens quite often to me. Below are things that have worked for me in the past:
- Restart your 3DS.
- Blow into the cartridge slot before you insert the game.
- Make sure the cartridge is clean.
- Keep removing and inserting the cartridge.
Also, have you tried putting in other games? Have they worked? You should also try to put your AS game card into another 3DS to clarify if it's a system problem or a game card problem.
Hope I helped!