Power bi rest api Export file error "Export report was called with an unsupported file format"

Hello!

While trying to test REST Api for export to file, i am facing the below issue.

Now I can export pdf,pptx, jpeg files, but I can not export  XLSX,CSV files.

https://docs.microsoft.com/en-us/rest/api/power-bi/reports/exporttofile

export step sample:

1.PostExportRequest

2.PollExportRequest

3.ExportPowerBIReport

4.GetExportedFile

"error": {
       "code": "InvalidRequest",
       "message": "Export report was called with an unsupported file format"
}