Based on the information provided in the email you received, it appears that your Microsoft 365 trial developer subscription has expired due to lack of development activity. According to the email, your admin access, subscription, and all your data will be deleted on 02/21/2024 (UTC). However, you can return to your dashboard sixty (60) days after your deletion date and request a new Microsoft 365 trial developer subscription.
If you use the account daily, it's possible that there was some issue with the development activity tracking. You may want to reach out to the Microsoft 365 Developer Program team to inquire about this and see if there is any way to reactivate your subscription.
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