I used FixedUpdate instead of Update for my movement. I also used GetAxis.
i did use getaxis but forgot about fixed update.. did u use time.deltatime?
This is what it would look like ish
float Speed = Whatever you want;
float Movex;
FixedUpdate()
{
Movex = Input.GetAxis("Horizontal");
transform.position += new Vector2(Movex * Speed, 0) * Time.deltaTime
}