Hi, Milan Panic I want to help you here to clear up the confusion.
To summarize your question:
You got this Message via Email from Microsoft and it tells you that the subscription with the Name "Access to Azure Active Directory" will be retired. Now you are confused if your existing resources in other subscriptions will be deleted as well.
I can tell you that you don't need to have worries here, the "Access to Azure Active Directory" subscription is a legacy subscription that Microsoft needs in the past to Access AzureAD. Today this subscription is no longer needed and does nothing anymore. When you want to delete the subscription earlier you can only do that by creating a support ticket. I recommend waiting for the retirement date when the subscription will be automatically deleted.
I hope I could help you to solve the question.
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