phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '21c3ad37faa170209f1cbcf2048f027f' 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 ('21c3ad37faa170209f1cbcf2048f027f', -1, 1768662041, 1768662041, 'd849d8ad', 5, 0, 0)

Line : 187
File : sessions.php