phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 'session_user_id'

INSERT INTO satshop_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('6c6e015e74af71f8467ba311017a0aad', -1, 1728603144, 1728603144, '2cc05fa1', -2, 0, 0)

Line : 189
File : sessions.php