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 ('9639788b68cf82eb5f9a93595721b657', -1, 1711678818, 1711678818, '2cc8d22b', 4, 0, 0)

Line : 187
File : sessions.php