Delay responding of particles

I need help with my script. I want my particle to start immediately when the ball hit the wall… I noticed there’s a delay like a second.( the ball bounce then the particle start.) I already tried to change all the parameters but still no luck.

void OnCollisionEnter(Collision collision) {
foreach (ContactPoint contact in collision.contacts)

{

Instantiate(sparks, transform.position, transform.rotation);
Debug.Log (“hit”);
}

}

Uncheck Prewarm option. Maybe this is what causing delay.
take a look at the docs.