Thank you for reaching out on the Microsoft Q&A forum.
Based on your question I understand that you are trying to delete your Azure CDN endpoint, but you are facing issue because Azure CDN endpoint CNAME is still associated with your custom domain.
Based on the documentation here this requirement was implemented to prevent dangling DNS entries and the security risks they create, starting from April 9th 2021, Azure CDN requires removal of the CNAME records to Azure CDN endpoints before the resources can be deleted. Resources include Azure CDN custom domains, Azure CDN profiles/endpoints or Azure resource groups that has Azure CDN custom domain(s) enabled.
In order to delete the custom domain, you need to delete the CNAME record for the custom domain, or update the CNAME record for the custom domain to a non-Azure CDN endpoint.
Based on your question I understand.
I do not own the domain xidekick.com anymore and I believe it no longer exists.
The domain might have been deleted and you do not own the domain anymore.
In this case you can try and bypass this check by running below PowerShell command which will register a feature for your Subscription which can help bypass the cname check. It is advised to wait for some time (15 - 20 mins) for feature to register and then attempt deleting the custom domain again.
Register-AzProviderFeature -ProviderNamespace Microsoft.Cdn -FeatureName BypassCnameCheckForCustomDomainDeletion
If this doesn't work, creating a support request can be helpful here as a support engineer can help remove cname check from the backend. Please let me know if you do not have a support plan, I can help you in this regard.
Hope this helps!
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