BAPI_MATERIAL_SAVEDATA field MARA-KZKFG not in ClientData

Hi There

I am using BAPI: BAPI_MATERIAL_SAVEDATA to create a material, it works properly, but I am unable to update field MARA-KZKFG, as it does not exist in BAPI_MARA, does anyone know of a way of updating this field using the BAPI?

Thanx

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