Are You enable the Enable PDF export which page need to be downloaded.Give yes to enable pdf export which is available in the page styling
This error “DOCGEN_FOR_WAIT_CONTENT_ERROR: Failed while waiting for page content” usually occurs when the Document Generation module cannot properly load or render the page you selected for generating the PDF. Even if your page has just a text box, the module still expects a fully rendered UI layout to capture it. To fix this, first ensure that the page you are using for PDF generation can be opened normally in your browser without any errors or visibility conditions. Next, make sure that the page is accessible for the document generation microflow, meaning it should not depend on user roles or session-based objects that may not exist during the generation process. If you are passing a data view object, confirm that it is available and committed before calling the “Generate Document” activity. Lastly, if your page contains dynamic content or widgets that load slowly, try adding a small delay (for example, 1–2 seconds) before the document generation step to let the content fully load. After applying these checks, the PDF should generate successfully without the waiting-for-content error.
This error means the DocumentGeneration worker’s headless browser timed out waiting for the page to reach the expected content/selector (page stayed blank, redirected, or never finished loading dynamic content). There is some issue with how it was implemented, It will be help if you can share some more info.
MeanWhile put a breakpoint and check what is happening, I hope you would have implemented as per the documentation.