How can I solve the issue: No module named 'simple_history'

I have my application and I would like to track the historical models for each modification in Django.
I have followed the instruction in this link: https://django-simple-history.readthedocs.io/en/latest/quick_start.html#install

However, I am getting the error ModuleNotFoundError: No module named ‘simple_history’
I uninstalled the package and reinstalled it but still getting the same error when I run the command python manage.py makemigrations.
Here is my model.py

import uuid

from django.db import models
from django.contrib.auth.models import User
# from django import forms
from django.forms.widgets import RadioSelect
from ckeditor.fields import RichTextField
from django.utils.translation import ugettext_lazy as _
from django.urls import reverse
from random import randint
from simple_history.models import HistoricalRecords

class CourrierArrive(models.Model):
    category_choice = (
        ('Entrant exterieur','Entrant exterieur'),
        ('Entrant locale ','Entrant locale'),
        ('Entrant locale interieur','Entrant locale interieur'),
    )

    statut = (
        ('Prioritaire','Prioritaire'),
        ('Rappel prévu','Rappel prévu'),
        ('Pour affectation','Pour affectation'),
        ('Pour signature','Pour signature'),
        # ('Envoyer','Envoyé'),
        ('Annulé','Annulé'),
        ('A imprimer','A imprimer'),
        ('A archiver','A archiver'),
        ('A rappeler','A rappeler'),
        ('A Encours de validation','Encours de validation'),
        ('Attente','En attente'),
        ('Rejecte','Rejeté'),
        ('Terminé','Terminé'),
        ('A ranger','A ranger'),
        ('A enregistrer','A enregistrer'),
        ('Avis favorable','Avis favorable'),
        ('Avis défavorable','Avis défavorable'),
        ('Pour facturation','Avis facturation'),
        ('Pour de traitement','Encours de traitement'),
    )

    nature_courrier = (
        ('Lettre avec A/R', 'Lettre avec A/R'),
        ('Lettre simple','Lettre simple'),
        ('Lettre remise en main propre','Lettre remise en main propre'),
        ('Facture','Facture'),
        )
    confidentiel_choice = (
        ('1','Oui'),
        ('2','Non'),
        )

    classer = (('Oui','Oui'),
            ('Non','Non')
            )
    reference = models.CharField(max_length=20, blank=False, unique=True)
    type_expediteur = models.CharField(choices=type_expediteur, max_length=50)
    expediteur = models.ForeignKey(Expediteur,on_delete=models.CASCADE ,null=True)
    destinataire = models.CharField(max_length=200, null=True, blank=False)
    nature_courrier = models.CharField(max_length=50, choices=nature_courrier)
    classer_sans_suite = models.CharField(max_length=3, choices=classer)
    objet = models.CharField(max_length=500)
    confidentiel = models.CharField(max_length=5, choices=confidentiel_choice)
    type_courrier = models.CharField(choices=category_choice, max_length=50)
    date_reception = models.DateField(auto_now_add=True)
    date_modification = models.DateField(auto_now=True)
    telephone = models.CharField(max_length=15)
    adresse_1 = models.CharField(max_length=500, blank=False)
    adresse_2 = models.CharField(max_length=500,blank=True)
    email = models.CharField(max_length=50,blank=True)
    nom_correspondant = models.CharField(max_length=200, blank=True)
    telephone_correspondant = models.CharField(max_length=15, blank=True)
    recepteur_courrier = models.ForeignKey(User, on_delete=models.CASCADE, null=True)
    statut = models.CharField(max_length=100, choices=statut)
    # document_scanne = models.FileField(upload_to='courrier_arrive/%Y/%m/%d', blank=True)
    commentaires = models.TextField(blank=True)
    history = HistoricalRecords()

    def __str__(self):
        return self.reference

settings.py file’s configuration

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'account',
    'courriers',
    'rolepermissions',
    'crispy_forms',
    'ckeditor',
    'simple_history',
]
CRISPY_TEMPLATE_PACK = 'bootstrap4'
MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.locale.LocaleMiddleware',
    'django.middleware.common.CommonMiddleware',
    # 'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'debug_toolbar.middleware.DebugToolbarMiddleware',
    'simple_history.middleware.HistoryRequestMiddleware',

]

What can be the error, please?

pip freeze results

asgiref==3.2.10
Django==3.1
django-ckeditor==6.0.0
django-cleanup==5.0.0
django-crispy-forms==1.9.2
django-debug-toolbar==2.2
django-discover-runner==1.0
django-js-asset==1.2.2
django-mathfilters==1.0.0
django-role-permissions==3.1.0
django-simple-history==2.8.0
django-tabination==0.4.0
fpdf==1.7.2
html5lib==1.1
Pillow==7.2.0
psycopg2==2.8.5
PyPDF2==1.26.0
pytz==2020.1
reportlab==3.5.47
six==1.15.0
sqlparse==0.3.1
Tether==0.1
webencodings==0.5.1
xhtml2pdf==0.2.4

Python version: Python 3.7.6

pip version: pip 20.2.2