Look at http://widukind-api.cepremap.org/api/v1/sdmx/EUROSTAT/data/demo_pjanbroad/A.NR.Y15-64.T.FR .
You should have only one series (I choose only one argument for each dimension), but here you have two series.
It is the same problem on the website if you go to Eurostat > demo_pjanbroad > Number > Total > Females > France you will obtain two series.