problem in size of pdf file converted through auto email of alv report

hello,

     I had develop a code for auto emailing a report to users as pdf attachement but when the file gets generated, its size becomes very small and the columns gets shrink and because of this the data is not visible in correct way. Plz suggest answers for this. As I already use this function also but getting a runtime error as Invalid subfield access: Offset too large

CALL FUNCTION 'SX_TABLE_LINE_WIDTH_CHANGE'

      EXPORTING

        line_width_src              = 134

        line_width_dst              = 255

      TABLES

        content_in                  = i_pdf

        content_out                 = l_attachment

      EXCEPTIONS

        err_line_width_src_too_long = 1

        err_line_width_dst_too_long = 2

        err_conv_failed             = 3

        OTHERS                      = 4.

    IF sy-subrc NE 0.

      MESSAGE s000(0k) WITH 'Conversion Failed'.

      EXIT.

    ENDIF.

Thanks in Advance.