On your Facebook page, edit your action button as shown below.
These are the steps for those on the Classic Version. If you do not see the Facebook page presented as you do here - You can find out here how to add the contact us from your New version!
If your page has a Home button then you are using the Classic version.
For steps on using the New Version, please see this article
Step 1
Click the Add a button button then choose Contact Us
Step 2
In the Action Button box, paste your Booking Link
Your booking link can be found In Online booking.
If you have further questions that haven't been answered in this article then please reach out to us on Live Chat via the chat bubble in the bottom right corner!