Please ensure that you have successfully run you app in development mode before putting it in production mode. To learn more about running Python apps in development mode, please checkout out this article : https://docs.n99panel.com/doku.php?id=python:dev-mode

Once you have tested you app in development mode, we can then undertake following steps to run your Flask app in production mode

Step 1 : Log into N99panel and click on 'Python'

Step 2 : Now click on 'Python Apps (production mode)'

Step 3 : Now further click on 'Add a Python App'

Step 4 : Then enter details of your Flask App as explained below

With these above mentioned steps, you can run your Flask app in production mode.