diff --git a/scripts/upgrade b/scripts/upgrade
index 68baab0..373ab46 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -88,7 +88,7 @@ chmod +x /etc/yunohost/hooks.d/post_app_install/${app}_sync_app_importer.sh
 
 if [ $(grep yunohost_sso_domain "$install_dir/wakka.config.php" | wc -l) = "0" ]; then
   SSO_DOMAIN=$(yunohost domain main-domain | sed -e 's/.*: //')
-  ynh_replace_string --match_string="wakkaConfig = array (" --replace_string="$wakkaConfig = array (\n  'yunohost_sso_domain' => '${SSO_DOMAIN}',\n);" --target_file="$install_dir/wakka.config.php"
+  ynh_replace_string --match_string="wakkaConfig = array (" --replace_string="wakkaConfig = array (\n  'yunohost_sso_domain' => '${SSO_DOMAIN}',\n);" --target_file="$install_dir/wakka.config.php"
 fi
 
 # ToDo : Add app importer config in wakka.config.php if it is not already there ?