I might be wrong but my understanding is it is the classic issue of two Cloudflare accounts with different nameservers where the registrar/registry insists on validating the new nameservers and what is currently announced (the previous ones) and refuses to go any further because of the mismatch.
Yes. DNS still worked after complete deletion of the domain from his account. So the information must still be in Cloudflare as when I try to redelegate the primary ns to bill.ns.Cloudflare.com my registrars system still tells me it will update the values to “gene and zoe” instead of (correct) “bill and lisa”… Very weird !
Your nameservers are bill and lisa? Cloudflare currently announces gene and zod and those must be from the previous account.
Again, I would bug the registrar as it is them who are the primary reason for that, however a) assuming the zone was removed I’d expect Cloudflare to stop announcing the nameservers and b) I am almost convinced that you will eventually have to contact Cloudflare.
Still, I’d bug the registrar though, just out of principle
Most European registrars will have limitations on assigning different nameservers within the same DNS in case the new domain was active in Cloudflare before. The reason for this is because our nameservers will always respond to the old domain nameserver values instead of the new pending zone.
In such cases it is not be possible to migrate Cloudflare without contacting Cloudflare support.
Before contacting our services, please make sure that any active Cloudflare account is on the deleted state. During this period you might need to revert to the original DNS in order to avoid any downtime.
In order to delete/deactivate the zone from Cloudflare, you can login to our dashboard and click on the ‘Advanced’ link from the Overview tab and click on the ‘Delete’ button.
Once this is done, please create a ticket to support from the Old zone asking the domain to be purged. Only then Cloudflare will be able to respond to the new pending zone nameservers and allow these registrars altering the nameservers.