Hi, @DeeSch
Welcome to the Microsoft Q&A forum!
Depending on your description, your mailbox may be blacklisted by Microsoft due to some reason, such as sending a large number of spam emails.
The first thing you need to do is confirm the status of your email address:
- Are you not receiving any emails from any sender?
- Does the sender receive a non-delivery report(NDR)? Can you provide me with a screenshot?
- If your mailbox is still able to accept some emails, then check for missing emails in “Junk Email”.
- Try adding email addresses from school and other important senders to your Whitelist or Safe Senders list.
- Contact Microsoft Phone Technical Support for faster and more effective instructions on how they can help you remove your email from blacklists or spam filters. Global Customer Service phone numbers - Microsoft Support
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