Destroy collider

Questions & Answers
1

The code does not work. I want to 2 in a collision object is deleted collider. Thank you in advance for your response.

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class RingsMove : MonoBehaviour {
	public float speed;
	public GameObject Rings;
	public Collider2D coll;
	void Start () {
	}
	void Update () {
		Rings.transform.Translate (new Vector3 (0, -1, 0) * speed * Time.deltaTime);
	}
	void OnCollisionEnter2D (Collision2D col) {
		if (col.gameObject.tag == "BackgroundTag") {
			Destroy (gameObject);
	}
		if (col.gameObject.tag == "RocketTag") {
			speed += 0.5f;
			Vector3 RingsPos = new Vector3 (Random.Range (-2.2f, 2.2f), 5.3f , 0f);
			Instantiate (Rings, RingsPos, transform.rotation);
			Destroy (coll);
		}
	}
}
2

@Mavina

I want to touch on the first collider was not deleted and the next time you touch removed.

if (col.gameObject.tag == "RocketTag") {
			speed += 0.5f;
			Vector3 RingsPos = new Vector3 (Random.Range (-2.2f, 2.2f), 5.3f , 0f);
			Instantiate (Rings, RingsPos, transform.rotation);
			Destroy (coll.gameObject.GetComponent<Collider>());
		}

With this code, an error occurs and the game stops.

ERROR:

UnassignedReferenceException: The variable coll of RingsMove has not been assigned.
You probably need to assign the coll variable of the RingsMove script in the inspector.
RingsMove.OnCollisionEnter2D (UnityEngine.Collision2D col) (at Assets/Scripts/RingsMove.cs:22)