phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'ff9337a5a9ab306af1133255a59d59a4' 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 ('ff9337a5a9ab306af1133255a59d59a4', -1, 1769083877, 1769083877, 'd849d879', -4, 0, 0)

Line : 187
File : sessions.php