Camera Collision Didn't Work. Please Help me...

  using System.Collections;
  using System.Collections.Generic;
  using UnityEngine;
  
  public class ThirdPersonCam : MonoBehaviour {
  
      [Header("Player to follow")]
      public Transform target;
  
      public float mouseSensitivity = 5;
      public float dstFromTarget = 14; // 9 atau 15
      //public float zoomSmooth = 100;
  
      public float maxDistance = 15;
      public float minDistance = 7;
  
      public bool smoothFollow = true;
  
      public float smooth = 5.0f;
  
      public Vector2 pitchMinMax = new Vector2 (-40, 85); // maksimum and minimum pitch rotation
      public bool lockCursor;
  
      public float rotationSmoothTime = .12f;
      Vector3 rotationSmoothVel;
      Vector3 currentRotation;
  
      float yaw, pitch;
      public bool state;
      public PlayerMovement playerMov;
  
      //cam colission var
      [Header("Layer(s) to include")]
      public LayerMask CamOclusion;  
      Vector3 dollyDir;
      Vector3 camPosition;
      public float distance;
  
  
  
      void Start () {
          
          if (lockCursor) {
              Cursor.lockState = CursorLockMode.Locked;
              Cursor.visible = false;
          }
  
          //cam collision
          dollyDir = transform.localPosition.normalized;
          distance = transform.localPosition.magnitude;
  
  
  
      }
  
      // Update is called once per frame
      void Update (){
          state = playerMov.swordState;
  
      }
  
  
  
      void LateUpdate () {
  
          yaw += Input.GetAxis ("Mouse X") * mouseSensitivity;
          pitch -= Input.GetAxis ("Mouse Y") * mouseSensitivity;
          pitch = Mathf.Clamp (pitch, pitchMinMax.x, pitchMinMax.y);
  
          Vector3 targetOffset = new Vector3(target.position.x, target.position.y, target.position.z);
  
          currentRotation = Vector3.SmoothDamp (currentRotation, new Vector3 (pitch, yaw), ref rotationSmoothVel, rotationSmoothTime);
          transform.eulerAngles = currentRotation;
  
          CamColisionFunc (ref targetOffset);
          Zoom ();
          transform.LookAt(target);
      }
  
      void Zoom(){
          if (state == true) {
              dstFromTarget = 9;
          }
          else if (state == false) {
              dstFromTarget = maxDistance;
          }
          camPosition = target.position - transform.forward * dstFromTarget;
          transform.position = Vector3.Lerp(transform.position, camPosition, Time.deltaTime * smooth);
      }
  
      void CamColisionFunc(ref Vector3 targetFollow){
          //#region prevent wall clipping
          Vector3 desiredCameraPos = Camera.main.transform.localPosition;
          RaycastHit wallHit;
  
          if (Physics.Linecast (targetFollow, desiredCameraPos, out wallHit,CamOclusion)){
              smooth = 10f;
              camPosition = new Vector3(wallHit.point.x + wallHit.normal.x * 0.5f, camPosition.y, wallHit.point.z + wallHit.normal.z * 0.5f);
              Debug.Log ("Hit Ray"+ wallHit.collider);
          } else {
              //Zoom ();
              //dstFromTarget = maxDistance;
              Debug.Log ("Not Hit");
          }
  
          //#endregion
      }
  }