Dear,
My client wants to take over the dns settings, so I’m in the process of moving the settings to another provider. I already updated the nameservers of the domain name registrar (iwantmyname), but in the Netlify domain panel it keeps saying that the domain is controlled by Netlify DNS. How can I undo this?
If you’re sure it is hosted elsewhere now, you can find a “delete DNS Zone” button at the bottom of the DNS management page for that zone (start from your team page, click Domains in the top nav, select the zone, scroll to the bottom of the page).
That will remove our system’s belief that we control the zone 
Found it! Thanks so much!