Their preferred method is to have you send "Direct Messages" to their Twitter support account: @AirbnbHelp. You'll have to have a Twitter account, obviously, and you'll need to follow them. If you're not familiar with Twitter, be aware that Direct Messages (also known as DMs) are not the same as public tweets. They're between just you and the person/entity that you send the message to. Also, they don't have the same tiny length limit as standard tweets.
After you contact @AirbnbHelp, they'll usually respond within minutes and exchange a few messages with you about your issue. If the issue is really complicated or if they can't solve it, they will bump you up to an email conversation or even a phone call. I've had very good experiences with them.
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