When deploying the api in heroku I would get this “Application labels aren't unique, duplicates: registration", the error I was encountering indicated that I have two applications with the same label 'registration' in my INSTALLED_APPSsetting in Django.
Solved it by checking the INSTALLED_APPS list in the Django settings file (usually settings.py) and removed one of the duplicated applications.
H10 error while deploying the api, the issue was that in the Procfile there was a name type of the app.
“Bad Request 400” error, to solve this issue in the setting added the correct name of my api in the Heroku “ALLOWED_HOSTS = ['localhost', '<your_app_name>.herokuapp.com']"