The message "Your account is under review" means that your account is being reviewed by Microsoft to ensure compliance with Azure's terms of service. This can happen for a variety of reasons, including suspicious activity, billing issues, or location-based restrictions.
In your case, it's possible that the location (Russia) is the reason for the account being blocked. Azure has different compliance and regulatory requirements for different regions and countries, and some services may not be available in certain areas.
As for registering a free account, it is possible that you may not be able to register for a free account while your account is under review.
You can contact Azure support to inquire about the status of your account, and to find out if there is anything that can be done to resolve the issue. They will be able to give you more information about why your account is under review, and what you can do to regain access to Azure services.
Make sure to provide them with your Azure account details, and the reason you think your account was blocked. It's also important to mention that Azure offers different account types and plans, you may be able to use free trial or pay-as-you-go plans.