Not sure what is causing this issue. I think a possible workaround would be start again, removing the .h and .cpp files completelly from your project and source folder, you will probably have to comment every reference to this files and its classes through the project. Right click the .uproject file and generate Visual Studio project files.
Then, you should compile with VS, start the engine editor and recreate the file with “File > New C++ class”. Paste the content back in the new files and recompile again. (using the autogenerated #includes)