Lock look rotation first person.

How can I lock look rotation on targets smoothly this code works but does not alter the y axis and the camera is tilted when all targets are down. How can I smoothly restor the original position of the camera? thanks in advance!

 void Update () {
         if(Input.GetKeyDown(KeyCode.Tab) || selectedTarget.GetComponent<EnemyHealth>().enemyDown == true){
             TargetEnemy();
         }
             
         myTransform.rotation = Quaternion.Slerp(myTransform.rotation, Quaternion.LookRotation(selectedTarget.position - myTransform.position), rotationSpeed * Time.deltaTime);
     }