diff --git a/sources/Coturn_config_rotate.sh b/sources/Coturn_config_rotate.sh
index 7f41aa4..2780efd 100644
--- a/sources/Coturn_config_rotate.sh
+++ b/sources/Coturn_config_rotate.sh
@@ -16,7 +16,7 @@ else
     external_IP_line="${external_IP_line/'__IPV4__,'/}"
 fi
 
-if [[ -n "$public_ip6" ]] && ynh_validate_ip 6 "$public_ip6"
+if [ -n "$public_ip6" ] && ynh_validate_ip6 --ip_address="$public_ip6"
 then
     external_IP_line="${external_IP_line/'__IPV6__'/$public_ip6}"
 else