I ran a test for 1 hour and a half, when generating the results NeoLoad got frozen, there was no way to close it so I terminated the process from the windows task manager, after that, the project can not be loaded anymore.
I wouldn’t know how to fix the issue, support would be needed for that but you might have a config.zip or config.bak or config.bak.timestamp in the projects directory, try unzipping that to a fresh directory and see if you have lost any work?