Multi-app deployment only shows blank page

I am trying to deploy a multi-app panel application but am greeted by a blank page.

Note I have the apps defined as individual functions as per the docs: (i.e. page1, page2, page3) and have pn.serve({...}) towards the end of my file that I serve using panel serve --...

There are no errors in the terminal logs but upon opening the page it remains blank. Any idea how I can fix this?