The number one reason for this is that the emails are going to a Junk or SPAM folder.
If using Microsoft Outlook, you can do the following:
Check the Junk Folder
Regularly check your Junk Email folder to make sure that important messages aren't ending up in there.
The Outlook Junk Email Filter automatically moves suspected spam to the Junk Email folder based on a variety of factors, including time and content of the email. If an email from a sender you want to whitelist has ended up in your junk folder, the process is simple.
Click on Show Content to view the body of the email.
Next, click Mark as Safe. The sender will be added to your Safe Senders list, and all future emails should go to your inbox.
Manually Unblock Senders
Beyond checking your Junk folder, look at your Blocked Senders list occasionally to make sure it doesn't contain friendly senders. To do this, choose Settings, then Options. In the left pane, choose Junk Email, then Blocked Senders. Select the address or domain that you want to unblock, and click the trash bin icon that's next to it. Do this for everything that you want to be removed, and click Save.
Manually Add Contacts to the Safe Senders List
You can also manually add email addresses or domains to your Safe Senders list in Outlook.com to permanently whitelist them. To do this, choose Settings, then Options. In the left pane, choose Junk Email, then Safe Senders. In the box, enter the email addresses or domains that you want to whitelist, and select the Add button. Click Save, and you're all set.
If using Mac Mail, you can do the following:
- Check the JUNK folder
On the left hand pane in Mail you will see a folder labeled JUNK". That is where spam and suspected Junk goes.
If you have mail that is NOT junk that you wish to view, click on the email message in the JUNK folder. At the top of the message is a message that says "Mail thinks this is Junk Mail". Click on Move to Inbox if you wish to put it back in your "normal" mail.
- You have several options on how to filter or change Mac Mail behavior, so be sure to check out these links:
* Reduce junk mail on Mac: https://support.apple.com/guide/mail/reduce-junk-mail-mlhlp1065/mac
* Tutorial for Mail on Mac: https://www.dummies.com/computers/macs/dealing-with-junk-mail-in-mac-os-x/
* Managing Spam on Mac: https://www.dummies.com/.../macs/how-to-manage-spam-e-mail-with-apple-mail/
* Configuring Mac Junk Mail settings: https://www.macworld.com/article/1155157/web-apps/mail-junk-mail-settings.html