Hi alisari55,
here again are not connected ways:

https://tools.geofabrik.de/osmi/?view=routing&lon=35.29561&lat=41.82043&zoom=9&baselayer=Geofabrik%20Standard&overlays=duplicated_edges%2Cduplicated_edges%2Cduplicated_edges_areas%2Cislands%2Cislands_car%2Cislands_bicycle%2Cislands_all%2Cunconnected_open_ends_1

What are your ideas, how to prevent creating these errors?

Bu hataların oluşmasını nasıl önleyebileceğimize dair fikirleriniz nelerdir?

Can I get your feedback here?

Can I get your feedback here?

Guido