Microsoft provides a guide on resources on how to block a mail sender, and how to manage blocked senders: . Please review the appropriate guide below.
For Outlook Desktop Apps for Windows
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https://support.microsoft.com/en-us/office/block-a-mail-sender-b29fd867-cac9-40d8-aed1-659e06a706e4
For Outlook for
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Mac
And for Outlook Web
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Access
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