Field Catalog is not found

Hi, friends I have used function module like this.

But Iam getting 'fieldcatalog not found' error.

CALL FUNCTION 'REUSE_ALV_HIERSEQ_LIST_DISPLAY'
   EXPORTING
*   I_CALLBACK_PROGRAM             = SY-CPROG
    IS_LAYOUT                      = WA_LAYOUT
    IT_FIELDCAT                    = IT_FCAT
    IT_SORT                        = IT_SORT
    I_DEFAULT                      = 'X'
    I_SAVE                         = 'X'
     I_TABNAME_HEADER               = 'IT_FINAL1'
     I_TABNAME_ITEM                 = 'IT_FINAL'
     IS_KEYINFO                     = KEY
   TABLES
     T_OUTTAB_HEADER                = IT_FINAL1
     T_OUTTAB_ITEM                  = IT_FINAL.