Rotation transform not sync smoothly


I am using

gameObject.transform.position = Vector3.Lerp(currentPosition, newPosition, 1);

to move my character which is working well. I am using following code to rotate my 2d character face 180 , y axis for face direction. Code is

transform.rotation = Quaternion.Slerp(startRotation, targetRotation, 35f);

This works, but the rotation is so slow it take like 2 sec to change face direction inside multiplayer game.Not sure why transform position sync instant but rotation is so slow for the same character. I am sure I am missing something. Can you guys plz help.