diff --git a/htdocs/core/lib/functionsnumtoword.lib.php b/htdocs/core/lib/functionsnumtoword.lib.php
index 6de1e69de1f..9295a6061c0 100644
--- a/htdocs/core/lib/functionsnumtoword.lib.php
+++ b/htdocs/core/lib/functionsnumtoword.lib.php
@@ -187,7 +187,7 @@ function dolNumberToWord($numero, $langs, $numorcurrency = 'number')
 
 	/*In dolibarr 3.6.2 (my current version) doesn't have $langs->default and
 	in case exist why ask $lang like a parameter?*/
-	if (((is_object($langs) && $langs->default == 'es_MX') || (!is_object($langs) && $langs == 'es_MX')) && $numorcurrency == 'currency') {
+	if (((is_object($langs) && $langs->getDefaultLang(1) == 'es_MX') || (!is_object($langs) && $langs == 'es_MX')) && $numorcurrency == 'currency') {
 		if ($numero >= 1 && $numero < 2) {
 			return ("UN PESO ".$parte_decimal." / 100 M.N.");
 		} elseif ($numero >= 0 && $numero < 1) {