phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '6fb3a0230c54f894ff7c8384603023d8' for key 1

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('6fb3a0230c54f894ff7c8384603023d8', -1, 1417033774, 1417033774, '365914f6', -1, 0, 0)

Line : 187
File : sessions.php