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 ('e4f257b23492d4546590a1e0c9c9685a', -1, 1711651083, 1711651083, '12ea8b95', -4, 0, 0)

Line : 187
File : sessions.php