phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '9399db7f371f5397bab482e55d0b02b4' 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 ('9399db7f371f5397bab482e55d0b02b4', -1, 1511108131, 1511108131, '3650e3bd', -1, 0, 0)

Line : 187
File : sessions.php