Capsule GameObject always standing up

I am Instantiating a Capsule GameObject and it always is standing up even if I change the rotation.

Here is the code I'm using to create it:

GameObject clone = GameObject.Instantiate(prefab, transform.position, transform.rotation) as GameObject;

and for the prefab's script:

rigidbody.AddForce(transform.forward * 856);

I tried changing the rotation on the object but nothing seems to work. Any suggestions?

Thank you.