Player(Sphere) is keep move to underground

i create roll a ball project games but when I put rigidbody and collider (for both of them) its still keep piercing and not in place that's must be. the point of my player keep to underground (y -1.00 more less) I think I already make the code safe but its still make that move to underground I just need that to move (x,y) and get the gravity (so I still can make the fall respawn) btw I using more less this code

  public static class Resource{
     public static float 5.0f;
     }
     Rigidbody body;
     
     void Start{
     body = GetComponent<Rigidbody>();
     }
     void FixedUpdate{
     float moveX = Input.GetAxis ("Horizontal");
     float moveZ = Input.GetAxis("Vertical");
     Vector 3 movement = new Vector3(moveX, moveZ);
     body.Addforce(movement * Resource.speed