As soon as your Exclusive Domain is created, you will need to verify the Exclusive Domain inside the Facebook Event Manager. The interface will walk you through these steps, but they are listed here for easy reference.
First open the "Pixels & Domains" dashboard in Everflow, and click on Configure Pixels -> Facebook (any subdomain is fine)
Click on the "Still need to verify your domain?" link at the bottom and follow all the steps up until the point where you can paste in your TXT record
Then, go to “Brand Safety → Domains” inside Facebook Ad Manager:
Click on “Add” to bring up the “Add a Domain” box:
Enter the new Exclusive Domain provided by GiddyUp and click “Add Domain”.
NOTE: This should be the core domain only (e.g. coolstuff.com). You are not adding subdomains such as aculief.coolstuff.com.
After you’ve added the domain, click on the “DNS TXT record” dropdown and copy the DNS TXT Record (it’s the entire string, starting with “facebook-domain-verification=”):
Navigate back to the "Pixels & Domains" dashboard, and paste the DNS TXT Record into the entry field (starting with “facebook-domain-verification=”): and click Save, then click Next to proceed
GiddyUp will add this DNS record to the Exclusive Domain automatically and you can then click “Verify” to complete the verification.