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 ('73613c0157c07644c6ff309b0c858bed', -1, 1542048147, 1542048147, '36a2a92d', 0, 0, 0)

Line : 193
File : sessions.php