We did see this issue last week where the registration was successful (it was), but is showing as failed, Registration failed after registering domain in Cloudflare - #7 by kurtis.coffman
Once you open a ticket, lmk the number here.
The issue with the domain running, I see an nxdomain error, is you have no DNS records in the DNS app of your cloudflare dashboard. Good adding dns records Tutorial available if you need assistance.