camera problem orbit/fallow

I have problem with simple script what fallow character and on mouse move camera rotation arround character, but problem is both cannot work toget. If comment transform.position = lookAt.position + startOffset; than rotation work fine but not fallowing camera , if comment transform.LookAt(lookAt.position); than following work fine but rotation not. How can make both to work?

  void Start()
     {
         lookAt = GameObject.FindGameObjectWithTag("Player").transform;
         startOffset = transform.position - lookAt.position;
     }
 
     void Update()
     {
 
         // move camera near character
         transform.position = lookAt.position + startOffset;
         transform.LookAt(lookAt.position);
 
         currentX = Input.GetAxis("Mouse X");
         currentY = Input.GetAxis("Mouse Y");
         currentY = Mathf.Clamp(currentY, Y_ANGLE_MIN, Y_ANGLE_MAX);
 
         transform.RotateAround(lookAt.transform.position, Vector3.up, currentX * OrbitSpeed);
        
 
 
         // if is first person camera on allow up/down
         //if (mycam.enabled)
         //{
         //    Debug.Log("work");
         //}
     }