phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'ff84d00bb2d90e79edf337f354d7dede' for key 'PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('ff84d00bb2d90e79edf337f354d7dede', -1, 1770272128, 1770272128, 'd849d802', -9, 0)

Line : 180
File : /www/includes/sessions.php