phpBB : Kritischer Fehler

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, is_robot, session_admin) VALUES ('6a26a108584b6586b0b51fbb2b802813', -1, 1519224594, 1519224594, '36a71dd0', 5, 0, '0', 0)

Line : 190
File : sessions.php