Do you have a / in the middle of your application title anywhere, the bundle display name, anything like that? If so, could you remove it and see if the issue goes away?
Please make sure that your packaged name matches the name of your project as well, in case you changed that any.
If that does not work for you, please create a new project and import your project files into the new project. Once you’ve done that, package the game and let me know if you run into the same issue.
Looking forward to hearing back from you, thanks!