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 ('a2aa94fb195c91a41655846c703f3a3d', -1, 1711614847, 1711614847, '03eb8b7a', 4, 0, 0)

Line : 187
File : sessions.php