phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '9879d48711ad79d1bac79090b51750ac' 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 ('9879d48711ad79d1bac79090b51750ac', -1, 1774576460, 1774576460, 'd849d86b', 1, 0, 0)

Line : 187
File : sessions.php