phpBB : Critical Error

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Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'ad47964787f11b5a1f50793a6310e530' 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 ('ad47964787f11b5a1f50793a6310e530', -1, 1781511788, 1781511788, 'd849d865', 0, 0, 0)

Line : 186
File : sessions.php