Unfortunately this happens, and sometimes quite often that is really disturbing for any seller at any auction platform. However this is something that can be expected in real life scenario, the buyer usually bid getting emotional with some domain & then finds himself having with no money or not interested any more kind of situation.
Coming to your question,
How to Proceed When you find a buyer Disappears after the Domain Auction ends at Flippa, and you Do not Find him anywhere or not replying, or not submitting payment to the system?
You visit the
sales completion area after the auction is over, and there you communicate with the buyer, telling him the procedure & helping him out with the submission of payment to the Flippa escrow, domain transfer & then release of payment to you after he receives the domain.
Well, definitely you start with greetings & congrats sort of formal messages to start a communication. If you dont receive a reply, the best thing that people suggest is to call the buyer at the mentioned number on the sales page or email him.
The best mindset is to think positive & talk positive with the buyer or whoever has won the domain at your auction.
If you dont receive a reply for few days, you can open a dispute if you like from the sales completion area.
Mention your case, and they will allow the other party to reply within 72 hours, and then flippa team decides the case on merit. If the reply does not come, you can relist your auction for free and the Flippa success fee will be waived.
This was one simple example of
dispute as per your question, but there can be many reasons for it.
However, I will always suggest you to talk positively even when you open the dispute that is officially required when the buyer disappears.
Hope it would help. Thanks for Reading.