It just happened that I faced the same issue with django 1.9.x, where I added a new field in my django app which triggered the same error as you mentioned above.
I logged into the dbshell
environment using
python manage.p dbshell # I know some use ./manage.py
and dropped all of my tables by running the following command within the dbshell
to drop the tables
your_psql=# drop schema public cascade;
This will drop all of your tables (be careful as you may lose your data, there away to keep the data!) and you will get a message right after executing this command tells you that all dropped. Right after that run the following command to create the schema again, otherwise your server will not run:
your_psql=# create schema public;
Then just do the
python manage.py makemigrations # you might not need this, and
python manage.py migrate
And you're ready to go.
I know this answer might be very late but I hope it will help someone.
Cheers