В чем ошибка в форме?

Question

[Rassul Nassyrov]

Ошибка:

return Database.Cursor.execute(self, query, params)
django.db.utils.IntegrityError: UNIQUE constraint failed: user_user.username

Models.py:

class User(AbstractUser):
    country = models.CharField(max_length=35, null = True, blank = True)
    city = models.CharField(max_length=35, null = True, blank = True)
    bio = models.CharField(max_length=150, null = True, blank = True)
    image = models.ImageField(upload_to = 'static/images', blank = True)

    def __str__(self):
        return self.username

class UserSettingsForm(ModelForm):
    User = get_user_model()
    class Meta:
        model = User
        fields = ['image']

Views.py:

imgform = UserSettingsForm(request.POST, request.FILES)
                if imgform.is_valid():
                    imgform.save()
                    return redirect('/user/profile')