Hi @Nepsys
Thank you for posting this in Microsoft Q&A.
The email you received from Microsoft indicates that your Microsoft Entra ID tenant has been inactive for more than 200 days. It's a reminder to take action regarding your Microsoft Entra ID tenant due to inactivity.
To avoid any problem in service, you should consider making a purchase or renewing your existing subscriptions before the specified deadline (January 17, 2025). This will help keep your tenant active.
Using Outlook email alone does not necessarily prevent your tenant from being classified as inactive. The inactivity notice is based on the overall activity within the Microsoft Entra ID tenant, not just email usage.
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.