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 ('92daa6f0263bc0420d109bfa9659fc38', -1, 1547752232, 1547752232, '22ea4c3b', 0, 0, 0)

Line : 189
File : sessions.php