diff --git a/htdocs/compta/facture/card.php b/htdocs/compta/facture/card.php
index cd1905f528f..925885e4e7a 100644
--- a/htdocs/compta/facture/card.php
+++ b/htdocs/compta/facture/card.php
@@ -2815,9 +2815,10 @@ if (!empty($conf->projet->enabled)) {
 $now = dol_now();
 
 $title = $langs->trans('InvoiceCustomer')." - ".$langs->trans('Card');
-$helpurl = "EN:Customers_Invoices|FR:Factures_Clients|ES:Facturas_a_clientes";
 
-llxHeader('', $title, $helpurl);
+$help_url = "EN:Customers_Invoices|FR:Factures_Clients|ES:Facturas_a_clientes";
+
+llxHeader('', $title, $help_url);
 
 // Mode creation