Raycast Hit suddently stopped working

Hi there guys i have been working on an over shoulder view for shooting those last days and i made a raycast to follow the crosshair and it was working perfectly but the camera was center on the head of the character during the zoom phase so i addes few offset and that's the only thing i touched with the camera.

Now suddenly the raycast isn't working anymore even when i tried to undo my last modification with the camera.

so i just can't figure out for the last hours what is going on and why isn't it working anymore.

Here is my code:

void Start () { Destroy (this.gameObject, LifeTime);

     Ray rayFromCam = Camera.main.ScreenPointToRay(Input.mousePosition);
     RaycastHit hitFromCam;    

     if (Physics.Raycast(rayFromCam, out hitFromCam))  
     {
          if (Input.GetButton("Fire3"))
         {
             this.gameObject.transform.LookAt(hitFromCam.point);
         }
     }
 }
 
 void Update ()
 {


     if(!this.gameObject || !this.gameObject.GetComponent<Rigidbody>())
     {
         return;
     }
         
     
     if (this.gameObject.GetComponent<Rigidbody>()) 
     {
         
         this.gameObject.GetComponent<Rigidbody>().velocity = this.gameObject.transform.forward * Speed;
         
     } 
     else 
     {
                         
         this.gameObject.transform.position += this.gameObject.transform.forward * Speed * Time.deltaTime;
         
     }
         
         
     
 }

Maybe you have allready witnesses that kind of problem .

:)