How do I know if a guest has paid online?

Their reservation details page

Also you would or should know what pre pay method you signed up for.

If none then they didn't prepay.

You also can contact partner support via 3 methods below

Never post action requests here, no one in BdC Partner Support team nor Finance Team have visibility here.

---

 

Simply report to BdC Partner Support , see below 3 methods. They will never see any post on the Partner Hub.

Message or Call BdC PartnerSupport 

1. In the extranet, go to the ‘Inbox’ tab.
2. Select ‘Booking.com messages’.
3. Right Pane - Click on ‘See Contact Options’. 
4. Choose Account
5. Now choose Other
6. Then at bottom , See all contact options, and click Message or Call
7. As there is no one number for all partners, the number for your nearest BdC Partner Support is then revealed.

Method 3:  *** public main lines via Where you can reach us