In order to troubleshoot why you are unable to send emails, follow the steps outlined below:

1. Check Spam Settings: Check whether the emails are being mistakenly sent to spam.
2. Check Outbox: Ensure that the emails are visible in your outbox.
3. Verify Account Setup: Verify that your account setup, username, and password are correct.
4. Check Internet Connection: Check whether your device has an active and reliable internet connection.
5. Update Software: Check that your software is up-to-date.