How to book a visa appointment in Da Nang when there are no available slots online?

When joining the waitlist, the nearest available date shown was 4 days out, but it's better to book a slot a month ahead — the system often offers an earlier opening within a week or two. Use a mail.ru or Yandex email, other providers may not receive the notification.

After joining the waitlist with an email address, the link with an updated calendar of open dates arrived about 5 days later — booked a convenient slot right after receiving it.

Trying to book directly showed no open slots. But 2 hours later, an email link arrived — a slot had freed up, opening the calendar with available dates.