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Just in case - did you replace the diacritics? Slashes?
Yes, though "Kraków" was selected from a dropdown list for the region. ("Małopolska" was an alternative I considered...) I tried the postcode with and without a dash.
There are websites in Spain that don’t accept my hometown due to the Ç and the ‘.. even sites with dropdowns suddenly refuse it :/ if you can manually enter instead of dropdown, drop the diacritics and accents
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