CALDAV filter and eventnr not working together

I’ve tried to retrieve the next two events with the same content but the second one is not found.

DateTime calAbfallGelb “Datum [%1$td.%1$tm.%1$tY]” { caldavPersonal=“calendar:Abfall type:EVENT eventNr:1 value:START filter-name:‘Gelb.+’”}
DateTime calAbfallGelbNext “Datum [%1$td.%1$tm.%1$tY]” { caldavPersonal=“calendar:Abfall type:ÊVENT eventNr:2 value:START filter-name:‘Gelb.+’”}

Looks like eventnr and filter are not working together, eventNr without filter-name works as expected.