phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '5b4ff47ca223b25c800e308995c20deb' 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 ('5b4ff47ca223b25c800e308995c20deb', -1, 1771050047, 1771050047, 'd849d88a', -4, 0, 0)

Line : 187
File : sessions.php