@Jason Donnell We have verified that the Advanced Management Portal was deprecated 5 patches ago as it was a legacy feature. You did not mention what you are trying to accomplish with your domain, but the two main features of the legacy portal were to manage the DNS and transfer the domain. The proper way to manage your DNS for your domain is via Azure DNS going forward. From the Overview page, select Manage DNS records.
In regard to transferring your domain, you can accomplish it using what's listed here and here.
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