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, session_admin) VALUES ('09394c4f3c50ea9112f1903e76623136', -1, 1328432969, 1328432969, '266bb3d2', -7, 0, 0)

Line : 172
File : sessions.php