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 ('c971b22e7a1a4f16c52f625a446b51c4', -1, 1768796115, 1768796115, 'd849d854', -4, 0, 0)

Line : 187
File : sessions.php