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 ('3de53bc704c6a0288e89881616ad57c6', -1, 1711713607, 1711713607, '12d4f2cb', 6, 0, 0)

Line : 187
File : sessions.php