phpBB : Critical Error

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, session_admin) VALUES ('13b1416c9db26ffa89a3776e2e560685', -1, 1708608264, 1708608264, '12cf81af', -4, 0, 0)

Line : 187
File : sessions.php