Object of class RE and language does not exist.

Dear All,

I make program, in which I explode BOM by using function module  CS_BOM_EXPL_MAT_V2.

CALL FUNCTION 'CS_BOM_EXPL_MAT_V2'

       EXPORTING

         capid                 = 'PP01'

         datuv                 = sy-datum

         emeng                 = 1

         mtnrv                 = itab2-matnr

         werks                 = 'PSML'

       TABLES

         stb                   = stb

         matcat                = matcat

       EXCEPTIONS

         alt_not_found         = 1

         call_invalid          = 2

         material_not_found    = 3

         missing_authorization = 4

         no_bom_found          = 5

         no_plant_data         = 6

         no_suitable_bom_found = 7

         conversion_error      = 8

         OTHERS                = 9.

     IF sy-subrc <> 0.

when I run it for all material the error is come Object <program name> of class RE and language does not exist.

Please tell reason and solution of this..

Regards,

Pooja