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 ('804dc8fa603e568c1a829c00a51657f8', -1, 1711671805, 1711671805, '03ee8e86', 6, 0, 0)

Line : 187
File : sessions.php