Drupal 8 : "@site" display "Drupal" instead of "site name"

Hello Drupal community !

I’ve just installed D8 avec somes years using D7.

First step : change the site name.
I’ve changed site name in /admin/config/system/site-information

But a default name ( => here: “Drupal” ) is always displayed.

“Drupal” is displayed when I call “@site” or “@s”. Any tips ? Any help ?
Thank you,

Drupal version: 

Source: https://www.drupal.org/taxonomy/term/22/feed