phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '818d08cf5e987d3486f1341e8717da47' for key 'phpbb_sessions.PRIMARY'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('818d08cf5e987d3486f1341e8717da47', -1, 1770444191, 1770444191, 'd849d88f', -4, 0, 0)

Line : 187
File : sessions.php