@Stan Dmitriev - Thanks for the question and using MS Q&A platform.
Access to the new Purview Portal is currently restricted to limited users and all the features are not available for all the customers. And all the features will enable it for our all the customers in a phased manner.
For more details, refer to MS Q&A thread addressing similar issue: How to access the Business domain and Data product sections?.
In case, if you want more details, please file a support ticket for deeper investigation and do share the SR# with us?
Hope this helps. Do let us know if you any further queries.
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