Raycast has offset when build is not in native aspect ratio

Raycast has offset when build is not in native aspect ratio (only in full screen mode) I have a script that adds black bars. However I am using mouseposition in raycast to find the position. Basically when the resolution has a different aspect ratio than 16:9 it creates 4:3 with black bars which somehow works for some resolution but when the scaling is too much it fails to work making me unable to click on gameobjects. Raycast script:

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 void CastRayOne() {
 Ray ray = Camera.main.ScreenPointToRay (Input.mousePosition);
 RaycastHit hit;
         if (Physics.Raycast (ray, out hit, 100)) {
             Debug.DrawLine (ray.origin, hit.point);
             Debug.Log ("Hit object: " + hit.collider.gameObject.name);
             if(hit.collider.gameObject.tag == "Character"){
                 CharacterHelper.SetActive(false);
                 CustomizerText_Character.text = hit.collider.gameObject.name;
             Instantiateposition = new Vector3(hit.collider.transform.position.x+2,hit.collider.transform.position.y,hit.collider.transform.position.z);
             Instantiatedobject = (GameObject)Instantiate (Customizer_Character,Instantiateposition,Customizer_Character.transform.rotation);
             Instantiatedbool = true; 
             TempChar = hit.collider.gameObject; 
             }