White screen after moving Symfony 4 project to another folder instead of a page, how to fix it?

Question

symfony

Installed the project (symfony/website-skeleton theproject) in the /var/www/project folder
Everything worked, the test page appeared at the address:
localhost project /public/
Moved the files to another folder, say /var/www/ project-new .
Now the address localhost project-new /public/ is a white screen.
What needs to be done after moving the project to another folder in order for the project to work?