1. Check your display settings and make sure the emails are sorted according to yoru preference.
2. Make sure the emails are set to be visible in the folder.
3. Ensure that you have the latest version of Outlook.
4. Check the settings of your email account to make sure that emails are being downloaded correctly.
5. Check and adjust any filters that may have been applied to the folder.
6. Go to the Outlook support website if none of the above steps resolves the issue.