unity – How can I repair Look rotation viewing vector is zero?

I used to be following a unity tutorial to make my character face within the place the digital camera is dealing with. After I completed the modifying the script, I bought an error at runtime saying, “Look rotation viewing vector is zero.” On the road :

  Vector3 viewDir = participant.place - new Vector3(rework.place.x, participant.place.y, rework.place.z);
    orientation.ahead = viewDir.normalized;

right here is the remainder of the code I wrote:

utilizing System.Collections;
utilizing System.Collections.Generic;
utilizing UnityEngine;

public class ThirdPersonCam : MonoBehaviour
{
     [Header("References")]
     public Remodel orientation;
     public Remodel participant;
     public Remodel playerObj;
     public Rigidbody rb;

     public float rotationSpeed;

    personal void Begin()
    {
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.seen = false;
    }

     void FixedUpdate()
     {
        Vector3 viewDir = participant.place - new Vector3(rework.place.x, participant.place.y, rework.place.z);
        orientation.ahead = viewDir.normalized;

        // rotate the playerObj
        float horizontalInput = Enter.GetAxis("Horizontal");
        float verticalInput = Enter.GetAxis("Vertical");
        Vector3 inputDir = orientation.ahead * verticalInput - orientation.proper * horizontalInput;

        if(inputDir != Vector3.zero)
            playerObj.ahead = Vector3.Slerp(playerObj.ahead, inputDir.normalized, Time.deltaTime * rotationSpeed);
     }
}