3012222 - Unknown Error when exporting document to Excel if the crosstab contains 2 structures

You are using a datasource which contains 2 structures for a Lumira document.

When you export the document to Excel, "Unknown Error" happens.

The following error is found in the log:

com.sap.ip.bi.base.exception.BIBaseRuntimeException: Unknown Error
 at com.sap.ip.bi.export.office.impl.excel2007.MsExcel2007Converter.getBinaryResultContainer(MsExcel2007Converter.java:164)
 at com.sap.ip.bi.export.impl.ExportController.getBinaryResultContainer(ExportController.java:457)
 at com.sap.ip.bi.export.controller.ExportResult.getExportResult(ExportResult.java:78)

...

Caused by: java.lang.IllegalStateException: Cannot add merged region X1:X2 to sheet because it overlaps with an existing merged region (X1:Y1).
 at org.apache.poi.xssf.usermodel.XSSFSheet.validateMergedRegions(XSSFSheet.java:480)
 at org.apache.poi.xssf.usermodel.XSSFSheet.addMergedRegion(XSSFSheet.java:413)
 at org.apache.poi.xssf.usermodel.XSSFSheet.addMergedRegion(XSSFSheet.java:367)

SAP Lumira

KBA , BI-LUM-DER , Lumira Designer , Problem