Stop an OnTriggerEnter event from happening if you quickly leave the trigger.,Is there a way to cancel an OntriggerEnter function if you leave the trigger quick enough?

I am creating a digging game for my class where you control a drill and dig through blocks of dirt. I am trying to make it so if you drill into a block of dirt for x amount of seconds, you will destroy the block. However, I want to make it so that if you quickly stop drilling the block, it will stop digging and not destroy the block. Right now, I have a timer that delays the destruction of the block, however, if you are not colliding with the trigger after the timer runs out, it still destroys the block. Any help would be appreciated, thanks!

 public class AttackTrigger : MonoBehaviour
 {
     public float digTimer;
     private bool timerOn = false;
     private void Start()
     {
 
     }
     private void Update()
     {
         if (timerOn == true)
         {
             digTimer -= Time.deltaTime;
         }else if (timerOn == false)
         {
             digTimer = 1.0f;
         }
     }
 
     IEnumerator OnTriggerEnter2D(Collider2D other)
 
     {
 
         timerOn = true;
         yield return new WaitForSeconds(1);
             if (other.tag == "Ground" && digTimer <= 0)
             {
            
                 Destroy(other.gameObject);
             timerOn = false;
             }
         
     }