where do i pay commission and tax bill of booking.com

By reading it as it literally tells you on the invoice how to, just below the line :

Payment Due: <DATE>

The next two paragraph explain and give bank details to use.

REMINDER : NEVER POST ANY ACTION REQUEST , ESPECICALLY CANCELLATION REQUESTS HERE, NOTHING WILL HAPPEN., EVER!

Simply report to BdC Partner Support , see below 3 methods.

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.

8.  

   *** public main lines via Where you can reach us

    

    

   ---