Object not landing flat with gravity

Hello ~

I have an object with a basic "jump" script that also rotates the object (kind of a backflip sort of motion). However whenever it lands on the ground at a certain angle (like shown in the picture), it does not level back to a flat position, but rather just stands up sort of unnaturally. I am trying to configure it so that what ever position it lands, it flattens out to the nearest edge, like how it would in real-world physics. Here is my script:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class PlayerController : MonoBehaviour {
6.  
7.     public float speed = 5f;
8.     public float jumpSpeed = 10f;
9.     private float movement = 0f;
10.     private Rigidbody rigidBody;
11.     // Use this for initialization
12.     void Start()
13.     {
14.         rigidBody = GetComponent<Rigidbody>();
15.     }
16.  
17.     // Update is called once per frame
18.     void Update()
19.     {
20.  
21.  
22.         movement = Input.GetAxis("Horizontal");
23.         if (movement > 0f)
24.         {
25.             rigidBody.velocity = new Vector2(movement * speed, rigidBody.velocity.y);
26.         }
27.         else if (movement < 0f)
28.         {
29.             rigidBody.velocity = new Vector2(movement * speed, rigidBody.velocity.y);
30.         }
31.         else
32.         {
33.             rigidBody.velocity = new Vector2(0, rigidBody.velocity.y);
34.         }
35.         if (Input.GetButtonDown("Jump"))
36.         {
37.          
38.             rigidBody.velocity = new Vector2(rigidBody.velocity.x, jumpSpeed);
39.             rigidBody.AddTorque(transform.forward * 50);
40.  
41.         }
42.     }
43. }