Shiny for Python error: Incomplete RStudio-Connect-App-Base-URL

I'm (attempting) to build and deploy my first Shiny for Python app. chatGPT made an app for me, and I deployed it to my shinyapps.io account from Posit Cloud. Now when the app launches on shinyapps.io, it disconnects from server and the log message is

2025-04-01T13:27:42.735421+00:00 shinyapps[14393933]: Incomplete RStudio-Connect-App-Base-URL:

any quick fixes for this?