Проблема с внешним ключом в фреймворке Django Rest

У меня такая проблема

insert or update on table "Auth_user_org" violates foreign key constraint "Auth_user_org_user_id_id_465bfad2_fk_auth_user_id"
DETAIL:  Key (user_id_id)=(1) is not present in table "auth_user".

вот мой model.py

class User(models.Model):
    id = models.AutoField(primary_key=True)
    FirstName = models.CharField(max_length=100)
    LastName = models.CharField(max_length=100)
    mail = models.CharField(max_length=100)

    def __str__(self):
        return str(self.id)

class Organization(models.Model):
    id = models.AutoField(primary_key=True)
    name = models.CharField(default='0000000',max_length=100)
    type = models.CharField(default='0000000',max_length=20)

    def __str__(self):
        return str(self.id)


class User_org(models.Model):
    id = models.AutoField(primary_key=True)
    user_id = models.ForeignKey(User,related_name='UserInfo', on_delete=models.CASCADE)
    organization_id = models.ForeignKey(Organization,related_name='orginfo',on_delete=models.CASCADE)
    def __str__(self):
        return str(self.user_id)

невозможно добавить в User_org, user_id и organization_id.

что такое решение?

organization = models.ForeignKey(Organization,related_name='orginfo',on_delete=models.CASCADE)