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 ('ff36d0993085ad9d84d8a532f78c63cc', -1, 1711624961, 1711624961, '23ade9b0', -4, 0, 0)

Line : 187
File : sessions.php