phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'c4c2ea07b112ee5682df703ac2359aad' for key 1

INSERT INTO phpbb2_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('c4c2ea07b112ee5682df703ac2359aad', -1, 1490596941, 1490596941, '369e6d59', 19, 0, 0)

Line : 187
File : sessions.php