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 ('0921bb01e69e1b14c3e0de121348ee38', -1, 1591413978, 1591413978, '22e83ed1', 1, 0, 0)

Line : 187
File : sessions.php