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 ('6e716b25df514efb7a5e08adbf20e3a1', -1, 1714024389, 1714024389, '0391b2f0', 4, 0, 0)

Line : 187
File : sessions.php