How do I set up subdomains to work with my app?

I have an app that works perfectly with my regular domain. I recently added some subdomains that direct to the same app. However, going to the actual subdomain displays the Coming Soon page from PythonAnywhere. Any idea how to fix this?

Subdomains are not currently supported on PythonAnywhere. If you want a site, you'll need a web app at the address.