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 ('012b7729d7ff37e7a7cdd0ce16ac9fd1', -1, 1728633303, 1728633303, '03ec56b8', -8, 0, 0)

Line : 187
File : sessions.php