phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '9ff6ff1bd02194120135d852fd3d6cbd' for key 'PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('9ff6ff1bd02194120135d852fd3d6cbd', -1, 1771826426, 1771826426, 'd849d8de', 41, 0, 0)

Line : 187
File : sessions.php