diff --git a/NationalRailwayLine/schema.json b/NationalRailwayLine/schema.json
index 05a813d..f6744dd 100644
--- a/NationalRailwayLine/schema.json
+++ b/NationalRailwayLine/schema.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "http://json-schema.org/schema#",
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
   "$schemaVersion": "0.0.1",
   "$id": "https://smart-data-models.github.io/dataModel.ERA/Certificate/schema.json",
   "modelTags": "ERA vocabulary, railway, train",