2D collision won't work?

Ok so i am using a spawner which makes copies of a prefab. The clones fall to the ground and they should die, but they don’t. The ground has a rigidbody2d and a box collider2d and so does my ball. Here is some of my code.
public class DestoryPlayerScript : MonoBehaviour {

void OnCollisionEnter2d (Collider2D other)
{
	Destroy (this.gameObject);

}

}

public class SpawnBallOnKeyPress : MonoBehaviour {

public GameObject Ball;
// Use this for initialization
void Start () {
	
}

// Update is called once per frame
void Update () {
	if (Input.GetMouseButtonDown (0)) {
		Instantiate (Ball, transform.position, Quaternion.identity);
	}
}

}

Does your prefab that you’re spawning have a rigidbody? According to the Unity collision matrix that would be necessary for the collision to be registered: Unity - Manual: Introduction to collision

Areleli

Case-sensitivity matters. The callback is called OnCollisionEnter2D not OnCollisionEnter2d.