If you are experiencing issues with sending emails, make sure your network connection is stable and you have a strong signal. If you use Wi-Fi, please try connecting to another network to see if it resolves the issue.
After sending an email, please don’t immediately quit Spark. It supports the Undo option, which is available for the 5 seconds after you press Send. The app actually sends an email only after this timed delay.
If your email is stuck in the Outbox folder and the solutions above don’t work, please contact our support team and provide the detailed app logs which will speed up the investigation.