Here is a list of troubleshooting tips for understanding why your emails may not be showing up in the correct date order:

1. Ensure your computer’s system date is set correctly
2. Check that your email application is set to the correct date order
3. Check your email provider’s sorting settings
4. Check your email filtering settings for any rules having an effect on incoming emails
5. Ensure your email inbox is not overloaded and causing issues with sorting