استخدامُ Outlook لنظام Android لإدارةِ البريدِ الإلكترونيِّ الشخصيِّ والتقويم
Sorry, but this is not something that can be checked from the forum side. Since you are still able to receive messages from other servers, it is important to confirm directly with the sender’s support team. In many cases, the issue is that the account information was changed on their side, so the messages may no longer be going to your Microsoft email address even though it appears that way.
Also, please check your Outlook.com settings in Microsoft Edge. Sign in to Outlook.com, click the gear icon in the upper-right corner, and open Mail settings. Then review Rules and delete any rule you did not create, especially anything that forwards, deletes, or moves messages automatically. After that, check Forwarding and IMAP to make sure no unknown forwarding address has been added. If you find an address that is not yours, remove it immediately.