Error when player trying to take damage from a hazard

Hi guys, I am currently working on a game that includes a health system. As part of the game, when the player runs into a saw they take damage, managed by an already set-up "modifyHealth" action. However, when the player collides with the saw, I instead get the error:

"NullReferenceException: Object reference not set to an instance of an object SawBlade.OnTriggerEnter (UnityEngine.Collider c) (at Assets/Scripts/SawBlade.cs:14)"

Here is the code in question:

 using UnityEngine;
 using System.Collections;
 
 public class SawBlade : MonoBehaviour {
 
     public float speed = 300;
     
     void Update () {
         transform.Rotate (Vector3.forward * speed *Time.deltaTime, Space.World);
     }
 
     void OnTriggerEnter(Collider c) {
         if (c.tag == "Player") {
             c.GetComponent<Health>().modifyHealth(-10);
         }
     }
 }

Does anyone know what could possibly be the problem?

Thanks!