Why doesn't PHP define __DIR__ correctly?

Question

linux

Good afternoon. on the linux server there is a config directory /var/www/project/common/config in this directory there is a
main-config.php file
and there are also (hidden) subfolders created not by me, but by the system, i.e. by writing ls -a I get a list of files + hidden ones, and there are also subfolders:
..2021_04_06_03_48_30.786156983
which contain the same main-config.php file
by editing main-config.php in the /var/www/project/common/config directory and writing in it
var_dump(__DIR__); die; it shows for some reason /var/www/project/common/config/..2021_04_06_03_48_30.786156983/main-config.php
what's the matter and what am I doing wrong?