Set Exact Permissions (750)

A service script must be runnable by its owner and group but invisible to everyone else: owner rwx, group r-x, others nothing — that's mode 750 (rwxr-x---). The file /root/app/run.sh currently has the wrong permissions. Set it to exactly 750.

chmod 750 /root/app/run.sh

Grading reads the file's mode. (0 for others is the security point: no world access to the script.)