2nd level properties return NULL

[zeginis]

{cubiql{
  dataset_births {
    observations {
      page(first: 20) {
        observation {
          reference_area {
            label
            uri
          }
          reference_period {
            start
            end
            label
            uri
}}}}}}}

Result:

observation": [
              {
                "reference_area": {
                  "label": null,
                  "uri": "http://statistics.gov.scot/id/statistical-geography/S02000001"
                },
                "reference_period": {
                  "start": null,
                  "end": null,
                  "label": null,
                  "uri": "http://reference.data.gov.uk/id/year/1999"
                }
              },
...

The configuration I use:

{:geo-dimension-uri "http://purl.org/linked-data/sdmx/2009/dimension#refArea"
 :time-dimension-uri "http://purl.org/linked-data/sdmx/2009/dimension#refPeriod"
 :codelist-source "component"
 :codelist-label-uri "http://www.w3.org/2000/01/rdf-schema#label"
 :dataset-label-uri "http://www.w3.org/2000/01/rdf-schema#label"                    
 :schema-label-language nil}

[lkitching]

Fixed by cc45a99f677b1e911380eb4f492e483ec587b124