Character bug when jumping unity?

Question

C++ / C#

There is a character who must walk forward, backward and jump. But with a few jumps, he starts to stiffly sausage, he starts to fly away in different directions and spin, how can this situation be corrected?

Thank you very much

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Managament : MonoBehaviour  {



    private GameObject player; //Переменна объекта персонажа с которым будем работать.
   
    public int speed = 6; //постоянная скорость перемещения персонажа
    public int jump = 3; //Высота прыжка

    public Animation animation; // Анимация



    void Start () {
        player = (GameObject)this.gameObject; //Задаем что наш персонаж это объект на котором расположен скрипт
    }


   
    void Update () {
        
        animation = GetComponent<Animation>();

        if(Input.GetKey (KeyCode.A)) {
            player.transform.position += player.transform.right * speed * Time.deltaTime; //перемещаем в лево
            animation.Play("running");
        }
        if(Input.GetKey (KeyCode.D)){
            player.transform.position -= player.transform.right * speed * Time.deltaTime; //перемещаем в право
            animation.Play("running");
        }
        if(Input.GetKey (KeyCode.Space)) {
            player.transform.position += player.transform.up * jump * Time.deltaTime; //Прыгаем
            animation.Play("jump");
        }
        
    
    }

}

Answer 1

Probably you are not saying something, when you jump (by the way, this is not a jump at all), the object simply rises while you press the space bar. There is no more logic there.
But if you use physics there (which you kept silent about), then the objects must be moved by physics, and not change its coordinates.

Answer 2

Try to disable rigidbody freeze rotation in z