Could not insert search results

DEBUG MODE

SQL Error : 1062 Duplicate entry '1649624958' for key 'PRIMARY'

INSERT INTO phpbb_search_results (search_id, session_id, search_array) VALUES(1649624958, 'b2c1ad8ae9b05fcdbc2505f6e2c14b6f', 'a:7:{s:14:"search_results";s:187:"13353, 13355, 13362, 13384, 13430, 13432, 13539, 13584, 13625, 13646, 13950, 13959, 13993, 14088, 16745, 16787, 16790, 16810, 16890, 16905, 16907, 16938, 16960, 16961, 16963, 16996, 17276";s:17:"total_match_count";i:27;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