Kindly follow these steps:

• Delete all migration files
• Truncate the django_migrations table
• comment the new boolean field
• run python manage.py makemigrations
• run python manage.py migrate --fake
• Uncomment the boolean field
• run python manage.py makemigrations
• run python manage.py migrate

Generally these steps solve any kind of migration problem

An another reason can be if you are using django_rest_framework then the serialiser too needs to be updated as per your model change.

Source: https://stackoverflow.com/a/51881452/6396981