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 ('787c5e9d31e2b5ec2d0d9d83accdea90', -1, 1711701014, 1711701014, '12ea9ac5', 4, 0, 0)

Line : 187
File : sessions.php