Deploying flask on app platform doesn't work after deploying

I’ve changed somethings on my local Flask app to adapt it when deploying like installing gunicorn and adding:

"if __name__ == "__main__":
    app.run(host='0.0.0.0', port=os.environ.get('PORT', 8080))"

to properly run my webapp. After a successful deployment I go to the default DigitalOcean url for the app and I see this message: “We encountered an error when trying to load your application and your page could not be served. Check the logs for your application in the App Platform dashboard.”

In my runtime logs I just see this:

[bookingssite] [2024-05-09 13:44:11] [2024-05-09 13:44:11 +0000] [1] [INFO] Listening at: http://0.0.0.0:8080 (1)
[bookingssite] [2024-05-09 13:44:11] [2024-05-09 13:44:11 +0000] [1] [INFO] Using worker: sync
[bookingssite] [2024-05-09 13:44:12] [2024-05-09 13:44:12 +0000] [18] [INFO] Booting worker with pid: 18

and then a lot of booting workers. This is how I load my sqlite database:

app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'data.sqlite')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db = SQLAlchemy(app)
Migrate(app,db)

I’ve also selected the right port when setting up the app platform. What’s the problem here?