phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry 'f9dd78a70701a0a7e57aa741be059649' 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 ('f9dd78a70701a0a7e57aa741be059649', -1, 1516450559, 1516450559, '36e2295b', 0, 0, 0)

Line : 187
File : sessions.php