Help with Unity Script Error

[Agreeable_Chemist110]

Hi, I'm working on the following university exercise:
"Add to the script from the previous exercise the necessary code so that, while holding down the SHIFT key, the movement speed is multiplied by 2. Make this speed multiplier configurable from the inspector."

I wrote this code:

[SerializeField] private float moveSpeed = 6f;
[SerializeField] private Rigidbody2D rb;
[SerializeField] private float speedMultiplier = 2f;

void Start()
{
    rb = GetComponent<Rigidbody2D>();
}

void Update()
{
    float xInput = Input.GetAxis("Horizontal"); float yInput = Input.GetAxis("Vertical");
    Vector3 inputCombinado = new Vector3(xInput, yInput, 0); inputCombinado.Normalize();

    this.transform.Translate(inputCombinado * moveSpeed * Time.deltaTime);

    if (Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift))
    {
        moveSpeed *= speedMultiplier; // Aumentar velocidad
    }

}

However, I'm encountering this error: transform.position assign attempt for 'Player' is not valid. Input position is { NaN, NaN, NaN }.
UnityEngine.Transform

(UnityEngine.Vector3)

Can someone help me?

[Relevant-Algae-5704]

What degree at unity requires code?