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 ('bd6806cca4889b5664cd5fc51a31d946', -1, 1607208765, 1607208765, '12d6171e', -9, 0, 0)

Line : 187
File : sessions.php