Player character moves downwards in top-down game,Player goes down continously

I'm making a top-down survival game like Don't Starve, but I only have basic Unity knowledge and I'm a dumb boy, so I copied a tutorial (the tutorial in question is www.youtube.com/watch?v=KG_XBc2a6-4)

Every time I start the game, the player character moves downwards very slowly. Constantly. So much so that it falls off the screen if ignored. Is there a way to stop this from happening? The person doing the tutorial didn't seem to have any issues.

The code in question is:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Mouvementsseseseseses : MonoBehaviour
 {
     private Rigidbody2D rb;
     private Animator anim;
     public float MovementSpeed;
     private Vector2 MovementInput;
 
     private void Awake()
     {
         rb = GetComponent<Rigidbody2D>();
         anim = GetComponent<Animator>();
     }
 
 
     private void Update()
     {
         Move();
         Animate();
     }
 
 
 
     private void Move()
     {
         float Horizontal = Input.GetAxisRaw("Horizontal");
         float Vertical = Input.GetAxisRaw("Vertical");
 
 
         if (Horizontal == 0 && Vertical == 0)
         {
             rb.velocity = new Vector2(0, 0);
             return;
         }
 
         MovementInput = new Vector2(Horizontal, Vertical);
 
         rb.velocity = MovementInput * MovementSpeed * Time.fixedDeltaTime;
     }
 
 
     private void Animate()
     {
         anim.SetFloat("MovementX", MovementInput.x);
         anim.SetFloat("MovementY", MovementInput.y);
     }
 }
 

,So, I'm trying to make a top-down survival game, but I'm a dumb boi and I kinda just copied an 8-directional movement tutorial. I copied the code, and did everything the tutorial said to do, but when I play the game, the player character slowly goes down on the y-axis. WHy is this happening? I need help.

The code in question is:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Mouvementsseseseseses : MonoBehaviour
 {
     private Rigidbody2D rb;
     private Animator anim;
     public float MovementSpeed;
     private Vector2 MovementInput;
 
     private void Awake()
     {
         rb = GetComponent<Rigidbody2D>();
         anim = GetComponent<Animator>();
     }
 
 
     private void Update()
     {
         Move();
         Animate();
     }
 
 
 
     private void Move()
     {
         float Horizontal = Input.GetAxisRaw("Horizontal");
         float Vertical = Input.GetAxisRaw("Vertical");
 
 
         if (Horizontal == 0 && Vertical == 0)
         {
             rb.velocity = new Vector2(0, 0);
             return;
         }
 
         MovementInput = new Vector2(Horizontal, Vertical);
 
         rb.velocity = MovementInput * MovementSpeed * Time.fixedDeltaTime;
     }
 
 
     private void Animate()
     {
         anim.SetFloat("MovementX", MovementInput.x);
         anim.SetFloat("MovementY", MovementInput.y);
     }
 }
 

Big brain stuff. Also, the tutorial I followed is this: www.youtube.com/watch?v=KG_XBc2a6-4