Whenever I try to save the assets, some of them are just not be able to be saved. And if I turn off the project and reload, they are, of course, disappeared. This is making me so frustrated. Please help.
Make sure you disable windows real-time protection or grant access to UE5 to bypass the security. UE5 is very hostile towards most of the system protection software, because they are trying to block any suspicious created file that any software attempt to.
Another thing that you need to check is to make sure the file name is not duplicated or any file with the name. It might sound silly but I’ve experienced it myself.