I wnat to use OSM for a software for reverse geocoding and watch data on map.

That’s no problem, but when I call this link, the postcode is wrong:

The Postcode should be 42697, bu in the tag theres all information (postcode, city, street, housenumber), but I only want 42697. Should it be in this format, or is this wrong? I searched in JOSM, but everywhere is postal_code = 42697 and not in the “wrong” format…



The geocoder shows that the result is based on this way ID:

Your should get better result if the nominatim database deletes this way in the database.
The result is valid because a postcode can be different depending on the country and a postcode “42697 solingen landwehr 7” might be correct in other countries.