phpBB : Erro Crítico

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO f_activesessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('b9781d7e15f975a3947d83c5fa3a2519', -1, 1768505057, 1768505057, 'd849d8de', 8, 0, 0)

Line : 187
File : sessions.php