Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
Getting your nameservers back to Azure DNS
You can do this without the Azure resource. Your App Service Domains are registered through GoDaddy behind the scenes, and there's an account under the email on your Azure subscription even though Azure never shows it to you. Run a password recovery at GoDaddy's Domain Control Center against that address. If you get in, repoint the nameservers to your Azure DNS zone from there.
Getting the resource back into your resource group
That one is a support ticket. When the Azure resource goes but the registration survives, the domain management object stays orphaned against your subscription, and only Microsoft can clear it so the resource can be recreated. It isn't a portal action. Worth raising it as a migration issue rather than a deletion, since that's what actually happened and it points them at the right thing.
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