My original question started by asking if you were using routing.
But I deleted it because I thought that you would have been through that setting when you rebuilt the code.
Perhaps you didn't notice it because Wappler first posted in February 2019 about planning to integrate in the following Wappler release a brand new panel in the project set up steps devoted to Routing.
Rebuilding your code with Wappler since that Routing panel was added as a default feature probably introduced your error.