phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('fa7739c808f3d09c5d7a602c8709a5a5', -1, 1711707498, 1711707498, '23ac6eb3', 4, 0, 0)

Line : 187
File : sessions.php