Contact import ALWAYS creates duplicates


I am using the ‘Import into Contacts’ function to Import contacts from vcard into NextCloud V13.

Import is running fine. However it does not honor the uid. For every imported contact a new UID is created.
Even if i manually create a new contact in NextCloud, export the new contact as vcard and import the same unmodified (just exported vcard) again i get a duplicate contact with a new uid.

Is this really working as designed or did i miss something critical?