Could not insert search results

DEBUG MODE

SQL Error : 1062 Duplicate entry '1215694027' for key 'PRIMARY'

INSERT INTO phpbb_search_results (search_id, session_id, search_array) VALUES(1215694027, 'b2c1ad8ae9b05fcdbc2505f6e2c14b6f', 'a:7:{s:14:"search_results";s:88:"2056, 2057, 2058, 2071, 2191, 2197, 2198, 2199, 2212, 2583, 2837, 3129, 4929, 8124, 8174";s:17:"total_match_count";i:15;s:12:"split_search";N;s:7:"sort_by";i:0;s:8:"sort_dir";s:4:"DESC";s:12:"show_results";s:5:"posts";s:12:"return_chars";i:200;}')

Line : 700
File : search.php