Can't migrate to heroku (Ruby on Rails tutorial [Michael Hartl] chaper 10)

I am working through chapter 10 of the Hartl book. In the conclusion of this chapter, we reset the heroku database and then migrate. However when I run:

heroku run rails db:migrate

I get an error:

rails aborted!
StandardError: An error has occurred, this and all later migrations canceled:

PG::UndefinedColumn: ERROR:  column "password_digest_string" of relation "users" does not exist
: ALTER TABLE "users" DROP "password_digest_string"

Earlier in the tutorial, I removed a column called password_digest_string because it was named incorrectly and I didn't need it yet. It seems like rails is trying to delete the column again even though it isn't there anymore. I deleted the migration file that removed this column but it still is trying to drop it. What's also odd is that I've migrated the database several times since dropping that column and never had this issue until I reset it. Any suggestions?