Update BKTXT field of table BKPF

Hello,

I have a requirement where I need to update the BKTXT field of table BKPF, to do this I have written the following but when I execute it I am getting the error and looks like this is not the way to do it. Do you know any other BAPI/FM that I can use to update the BXTXT field of table BKPF based on the document number.

data: i_accchg TYPE STANDARD TABLE OF accchg,       wa_accchg LIKE LINE OF i_accchg,       wa_belnr TYPE bkpf-belnr. wa_accchg-fdname = 'BKTXT'.                " field that need to be updated wa_accchg-oldval = ' '.            " old value in that field if any wa_accchg-newval = 'TEST'.            " value that need to be updated APPEND wa_accchg to i_accchg. wa_belnr = '0990883998'. CALL FUNCTION 'FI_DOCUMENT_CHANGE'   EXPORTING     i_awtyp                    = 'BKPF'     i_awref                    = wa_belnr *   I_AWORG                    = ' ' *   I_AWSYS                    = ' ' *   I_KUNNR                    = ' ' *   I_LIFNR                    = ' ' *   I_OBZEI                    = ' ' *   I_BUZEI                    = *   I_BSEGC                    = *   X_LOCK                     = 'X'   TABLES     t_accchg                   = i_accchg * EXCEPTIONS *   NO_REFERENCE               = 1 *   NO_DOCUMENT                = 2 *   MANY_DOCUMENTS             = 3 *   WRONG_INPUT                = 4 *   OVERWRITE_CREDITCARD       = 5 *   OTHERS                     = 6           . IF sy-subrc <> 0. * Implement suitable error handling hereENDIF.

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