diff --git a/scripts/upgrade b/scripts/upgrade
index a8a7894..973d740 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -7,6 +7,7 @@ source /usr/share/yunohost/helpers
 set -eu
 
 # Retrieve arguments
+app=$YNH_APP_INSTANCE_NAME
 domain=$(ynh_app_setting_get "$app" domain)
 path=$(ynh_app_setting_get "$app" path)
 is_public=$(ynh_app_setting_get "$app" is_public)