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 ('d44d7547999f96de0921a23b7a63e4c2', -1, 1569051336, 1569051336, '23afbf96', 17, 0, 0)

Line : 187
File : sessions.php