diff --git a/htdocs/product/stock/class/api_productlots.class.php b/htdocs/product/stock/class/api_productlots.class.php
index 541077d61a0..b9e1a82b8b0 100644
--- a/htdocs/product/stock/class/api_productlots.class.php
+++ b/htdocs/product/stock/class/api_productlots.class.php
@@ -338,7 +338,7 @@ class Productlots extends DolibarrApi
 		}
 
 		if ($this->productlot->delete(DolibarrApiAccess::$user) < 0) {
-			throw new RestException(500, 'Error when delete Product lot : '.$this->productlot->error);
+			throw new RestException(500, 'Error when delete Product lot : '.implode(',', $this->productlot->errors));
 		}
 
 		return array(