You'll see an "Error" pop up that give you the option to transmit later. This appears when the internet and/or reception is not strong or internet switch off.
Below is what the pop up box look like:
1. Once you click "Transmit Later", the scan is saved.
2. You will need to scan an item to push the saved scans through. When you have internet on or strong reception.
3. If you notice that you are seeing these messages on a regular basis, please uninstall and reinstall the application.