To ensure emails are properly formatted and displayed correctly from a specific sender, please follow the below steps:

1. Add the sender's email address to the Safe Senders List using the Mail App.
2. Adjust any server-side settings to allow HTML formatting instead of plain text formatting.
3. Ensure the sender's email program is HTML compatible.
4. Check to see if the sender's email is marked as spam or junk.

Once the above steps have been completed, emails from the sender should now be displayed correctly.