how to pack the material into hanling unit

Hi ,

I have a requirement that, create HU and pack material to that created HU. I am trying to use BAPI_HU_CREAE to create the HU first and then HU_PACKING_AND_UNPACKING to pack the material into the HU. I am able to create the HU but not able to pack the Material into HU. Could anyone help me how to use those FM's to pack the material into HU inside the ABAP report.