phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '8c9dcf1c783e197cc7c0e11991e931e2' 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 ('8c9dcf1c783e197cc7c0e11991e931e2', -1, 1769364728, 1769364728, 'd849d814', -4, 0, 0)

Line : 187
File : sessions.php