set PnC connectorId = -1 if preparing connector not found

EVCB_OCPP.WSServer/Service/OuterBusinessService.cs

@@ -283,6 +283,11 @@ namespace EVCB_OCPP.WSServer.Service
                         connectorId = connectorStatus.ConnectorId;
                     }
                 }
+
+                if (connectorId is null)
+                {
+                    connectorId = -1;
+                }
             }
 
             return string.Format("charging_auth?ChargeBoxId={0}&ConnectorId={1}&IdTag={2}", chargeBoxId, connectorId, idTag);

version.txt

@@ -1 +1 @@
-Docker_v1.1.20
+Docker_v1.1.21