Integrating with FlutterFlow using the "Trigger BuildShip Workflow"

I'm integrating with FlutterFlow using the "Trigger BuildShip Workflow" library and I am running into a "AssertionError: status code must be a number" JSON error in FF when testing a POST API Call (FF-->BS). Both platforms are connected. The FF configuration checksout (I think). I think the problem is how I have configured trigger in buildship. Can anyone help?