I upgrade my project from UE 5.1 to 5.4 and all include not working.
Its not only for one project, every my projects after upgrade cant find includes.
For small projects i can create new empty 5.4 project and transfer logic from old to new. But its not easy to do it for big projects.
Delete the Intermediate (in the project or plugin folder) and run Generate
Visual Studio project files in the context menu of the project file.