Problem with Mapping in SAP PI: Values missing in queue context.

Dear SAP PI experts,

I am getting an error message in mapping:

Cannot create target element /ns1:AS500_DT_Person. Values missing in queue context. Target XSD requires a value for this element, but the target-field mapping does not create one. Check whether the XML instance is valid for the source XSD, and whether the target-field mapping fulfils the requirement of the target XSD

I took the payload from message monitor and put in into the test application in Enterprise Service Builder. My Mapping looks like here:

The data comes from a JDBC connector and the data type is ZUCC_DATA_CNTCTN.resultSet. The target message type is AS500_DT_Person. When I delete the connection between the root elements at the tree in the mapping, the error will not show up but the target XML is empty, no data will be transferred.

What might be the root cause?

Thanks,

André