Notice: Undefined index: id_gshoppingflux

[furetto]

I've got error 502 and these are the logs:
2020/02/17 16:10:22 [error] 12107#12107: *9 FastCGI sent in stderr: "PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/shop/src/Adapter/Routing/LegacyHelperLinkBuilder.php on line 74 PHP message: PHP Notice: Undefined index: id_gshoppingflux in /var/www/sh 2020/02/17 16:10:22 [error] 12107#12107: *9 upstream prematurely closed FastCGI stdout while reading response header from upstream, client: 89.96.240.254, server: shop.XXXXXX.it, request: "GET /XXXXXXX/index.php?controller=AdminModules&configure=gshoppingflux&token=5ea21f1586eb3b177f023ea4f767674e HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.0-fpm.sock:", host: "shop.tabacco.it", referrer: "https://shop.XXXXXXX.it/XXXXXXXX/index.php/improve/modules/manage?_token=CHaz8e6vpS0AmRC9tROnHACHk-T2DwEasVrW1lNbWLw"