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 ('4979de13726712f7c8d5b90a52a113b6', -1, 1711711529, 1711711529, '36e29b97', 3, 0, 0)

Line : 187
File : sessions.php