Hi @29976883 ,
Welcome to our forum!
Are you using a Microsoft 365 account?
If so, as i know, If a user exceeds one of the outbound sending limits as specified in the service limits or in outbound spam policies, the user is restricted from sending email, but they can still receive email. You can contact admin to remove users from the Restricted users page in the Microsoft 365 Defender or in Exchange Online PowerShell. More information:
Remove blocked users from the Restricted users portal in Microsoft 365
In addition, i noticed that you added some personal information to the post, so I hid them. To avoid your privacy, please remember to hide your personal information in your replies.
Hope to help you!
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