@Dominik-Paebst
Thank you for your post!
When it comes to deleting your tenant with the requirement of License-based subscriptions or Azure Subscriptions remaining, can you make sure you don't have any subscriptions within your Azure Portal or Microsoft 365 portal?
Microsoft 365 - https://admin.microsoft.com/Adminportal/Home#/subscriptions
Azure Portal - https://portal.azure.com/#blade/Microsoft_Azure_Billing/SubscriptionsBlade
If you don't have any active subscriptions and are still having issues deleting your tenant, I'd recommend creating a support request for this issue since our support team can look further into your issue
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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