Blueprint Compilation Errors, Engine bug?

Whenever I update the structure I use that’s been reference in Game instance, the UI that reference the game instance variable will cause an error. this error only happens when I close the project and reopen and try to the run it. but there’s nothing wrong if I just refresh the node, it will work and play as normal. but when I save the project, reopen it again, and try to run it again, same error will pop up. no matter what I tried, it will not go away, everytime I need to manually refresh the node and it will compile and save no problem, but everytime reopen the project, same error happens over and over again. anything I did wrong or is it just an engine bug?


when I manually refresh the node, error is gone and play as usual, but when saved and closed the project, reopen and run it again, same error will pop up.

Please Help, I also tried to delete the saved and other temporary folder from the project folder, still not working. the error message comes out every time I reopen the project and try to run it the first time, when I refresh the nodes, it works, but next time reopen the file, errors come out again