EASY! die if touching for 3 seconds or more script?

I have this script that kills object , but I want the object to die only if touching the ground for 3 seconds or more. please help

using UnityEngine;
using System.Collections;

public class die : MonoBehaviour {

	void   OnCollisionEnter2D(Collision2D coll) {

	

			if (coll.gameObject.CompareTag ("Ground")) {
				Destroy (gameObject, 3);
			}
		}
}

Please try to use this script:

using System;
using UnityEngine;
    public class die : MonoBehaviour
     {
            private DateTime _startTimeOfTouch;
            private bool _collisionStarted = false;
    
            void OnCollisionEnter2D(Collision2D coll)
            {
                if (coll.gameObject.CompareTag("Ground"))
                {
                    _startTimeOfTouch = DateTime.Now;
                    _collisionStarted = true;
                }
                GetComponent<Rigidbody>().sleepThreshold = 0;
            }
    
            void OnCollisionStay2D(Collision2D coll)
            {
                if (_collisionStarted && (DateTime.Now - _startTimeOfTouch).Seconds > 3)
                {
                    Destroy(gameObject);
                }
                
            }
    
             void OnCollisionExit2D(Collision2D coll)
             {
                 _collisionStarted = false;
             }
        }