Hey,
thanks for the request and sorry for not getting back to you earlier.
Please make sure that you only enter the post code if it's a national shipment (both sent and received in NL). This is important as the app retrieves the information from different websites if you supply a post code.
If you still have issues with specific tracking IDs, please send them with all information you entered to deliveries@orrrs.de so I can take a proper look at it.