iQvoc does not export Concept Scheme labels

[EwaSniegowskaPCSS]

When I fill in fields in Scheme section: Preferred labels and Alternative labels this data are then not exported when issuing Export. Is this intended behaviour?

The label data are also ignored during import. E.g. I import data:

<https://bn-lit-skos.lab.dariah.pl/scheme> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/2004/02/skos/core#ConceptScheme> .
<https://bn-lit-skos.lab.dariah.pl/scheme> <http://www.w3.org/2004/02/skos/core#hasTopConcept> <https://bn-lit-skos.lab.dariah.pl/Literaturoznawstwo> .
<https://bn-lit-skos.lab.dariah.pl/scheme> <http://www.w3.org/2000/01/rdf-schema#label> "Test 01" .
<https://bn-lit-skos.lab.dariah.pl/scheme> <http://www.w3.org/2004/02/skos/core#prefLabel> "Test 02" .
<https://bn-lit-skos.lab.dariah.pl/scheme> <http://www.w3.org/2004/02/skos/core#altLabel> "Test 03" .
...

None of the labels is then showing in the Scheme section after import. I tried using rdf-schema:label also because that's what is added when you instruct skosify tool to add a label to the ConceptScheme.