Hi @Adrian24,
Log onto the ABNB site. At the top you'll see "Messages", click that and then you'll see your inquiry or booking request, click it. From there you'll be taken to a page where you can respond to the message and press "send". If it's a booking request, you'll get the options at the top of the page to accept or decline. If it's an inquiry, you'll see the options to pre-approve, decline or send special offer at the top.
Hope this helps!
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