diff --git a/htdocs/core/modules/delivery/mod_delivery_jade.php b/htdocs/core/modules/delivery/mod_delivery_jade.php
index 1d5b7edda29..7a0713025cf 100644
--- a/htdocs/core/modules/delivery/mod_delivery_jade.php
+++ b/htdocs/core/modules/delivery/mod_delivery_jade.php
@@ -157,7 +157,7 @@ class mod_delivery_jade extends ModeleNumRefDeliveryOrder
 		if (empty($date)) {
 			$date = dol_now();
 		}
-		$yymm = strftime("%y%m", $date);
+		$yymm = dol_print_date($date, "%y%m");
 
 		if ($max >= (pow(10, 4) - 1)) {
 			$num = $max + 1; // If counter > 9999, we do not format on 4 chars, we take number as it is