phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '6869b9fad03e321240fb3cab8588304c' for key 1

INSERT INTO phpbb2_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('6869b9fad03e321240fb3cab8588304c', -1, 1495776440, 1495776440, '17149306', 21, 0, 0)

Line : 187
File : sessions.php