django migrate subquery returned more than 1 value

Question

I'm using Django and SQL Server to create a simple django model as:

from django.db import models

class Person(models.Model):
    first_name = models.CharField(max_length = 40)
    last_name = models.CharField(max_length = 40)

    class Meta:
        managed = False
        db_table = 'api].[persons'

My migration file is:

from django.db import migrations, models

class Migration(migrations.Migration):

    initial = False

    dependencies = [
    ]

    operations = [
        migrations.CreateModel(
            name='Person',
            fields=[
                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, 
 verbose_name='ID')),
                ('first_name', models.CharField(max_length=40)),
                ('last_name', models.CharField(max_length=40)),
            ],
            options={
                'db_table': 'api].[persons',
                'managed': False,
            },
        ),
    ]

Now when i try to run migration using migrate command, I'm getting error as:

Traceback (most recent call last):
  File "C:\Python3\lib\site-packages\django\db\backends\utils.py", line 83, in _execute
    return self.cursor.execute(sql)
 File "C:\Python3\lib\site-packages\sql_server\pyodbc\base.py", line 547, in execute
   return self.cursor.execute(sql, params)
 pyodbc.Error: ('21000', '[21000] [Microsoft][ODBC Driver 17 for SQL Server][SQL Server]Subquery 
returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression. (512) (SQLExecDirectW); [21000] [Microsoft][ODBC Driver 17 for SQL Server][SQL Server]The statement has been terminated. (3621)')

This is what my Database settings look like:

    DATABASES = {
        'default': {
        'ENGINE': 'sql_server.pyodbc',
        'NAME': 'Myname',
        'HOST': myhost,
        'USER': 'user',
        'PASSWORD': 'pass',

        'OPTIONS': {
            'driver': 'ODBC Driver 17 for SQL Server',
            'unicode_results': True,
        }
    },

    'test': {
        'ENGINE': 'sql_server.pyodbc',
        'NAME': 'name',
        'HOST': 'host2',
        'USER': 'test_user',
        'PASSWORD': 'test_pass',

        'OPTIONS': {
            'driver': 'ODBC Driver 17 for SQL Server',
            'unicode_results': True,
        }
    },
}

I've not used sub-query anywhere in my model but I'm not sure why I'm getting this error.

Note: Django==2.1.15 django-pyodbc-azure==2.1.0.0