I have a SharePoint site with Excel sheets which requires people from external organisations to fill in specific data into every month. I would like to create a flow on Power Automate to send e-mail notifications to those external parties if they forgot to fill in their data.
At the moment, this is what my flow looks like.

I am genuinely very new to this platform and I am not sure how to proceed. The flow works whenever the Excel sheet is modified - hence the TRUE works and I receive an email when I run the test. But how do I test the FALSE condition?