Django: Extended User Model not saving changes to database

Question

I have the following extended user class in models.py:

Pro_User(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    access = models.BooleanField


    def access_update(self, Activated:bool):
          self.access = Activated
          self.save()

However when I call access_update(True) in the shell it does not store the changes permanently, in the next shell session it is just BooleanField again.

Any tips are appreciated :)

I tried a lot of different things I found on StackOverflow already