phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'c40ff4da2dbf2f79d6605d29e063ed51' 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 ('c40ff4da2dbf2f79d6605d29e063ed51', -1, 1768313913, 1768313913, 'd849d81c', -4, 0, 0)

Line : 187
File : sessions.php