phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('e0e517888a7032e36d406067c8d0eb94', -1, 1427805204, 1427805204, '36c54161', 0, 0)

Line : 158
File : sessions.php