Delete the maximum ID row
MySQL allows a join in a DELETE statement. You can use this feature to first get a derived table, similar to the query you have that finds all maximum ids for groups that have more than 1 row, then join this derived table to the table itself.

The following assumes that (tbl_cod_rpt_id) is the primary key of the table:

DELETE 
    t.*
FROM 
    ( SELECT awb_no, MAX(tbl_cod_rpt_id) AS tbl_cod_rpt_id
      FROM tbl_cod_rpt_COPY
      GROUP BY awb_no
      HAVING COUNT(*) &gt; 1
    ) AS dup
JOIN 
    tbl_cod_rpt_COPY AS t
  ON 
    t.tbl_cod_rpt_id = dup.tbl_cod_rpt_id ;