Cannot use flask with db command

[redezvous2004]

I try to search for solution and try but still got this error. I don't know how to solve this?

[miguelgrinberg]

You did not provide enough information to tell you what's wrong, but in almost all cases this is caused by an incorrect set up of your Flask application, and is not related to Flask-Migrate.

I would start by checking your FLASK_APP environment variable as a first step to troubleshoot this.