phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'ffd23f5b61a55e6fa68108f6c041b348' 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 ('ffd23f5b61a55e6fa68108f6c041b348', -1, 1770984405, 1770984405, 'd849d809', -4, 0, 0)

Line : 187
File : sessions.php