Setting up FB Business manager
If you are using a custom domain for your HVL site and want to setup FB ads using the conversion objective then you need to setup a FB business manager account, add your existing ad account and business page to it, and then you would be able to verify your domain and add the needed events.
Let's get started.
Create a business manager account here: https://business.facebook.com/overview
After creating the business manager, you will need to verify the email address you used during setup.
After verification your business manager will open up.
It will say no ad accounts and no pages. You will need to add your existing ad account page to your business manager.
Go here https://business.facebook.com/settings/ad-accounts?b to add your existing ad account.
Click Add. Then click add an "ad account." Enter your existing ad account ID which you can get from Facebook.com/ads/manage.
After the ad account is added to business manager you need to add your page.
Go here https://business.facebook.com/settings/pages click add, then click add existing page. Add the URL of your business page.
Now that the ad account and page have been added, you need to add yourself to them.
To add yourself to your ad account go here https://business.facebook.com/settings/ad-accounts?b and click on add people.
Click your name and select manage ad account.
Add yourself to your page as well.
After you setup business manager correctly you will then be able to verify your domain and setup ads with the conversion events after the iOS update.