delete from Table_Name a
where
   a.rowid >
   any (select b.rowid
   from
      Table_Name b
   where
      (A.column_name_1 = B.column_name_1)
   and
      (A.column_name_2 = B.column_name_2)
   );


commit;

Example: Student table have three column id, name and age. We want to delete duplicate for same id and name

delete from student a
where
   a.rowid >
   any (select b.rowid
   from
      student b
   where
      (A.id = B.id)
   and
      (A.name = B.name)
   );


commit;