When using the Email option as an upload method, it is possible, for various reasons, that files are not received in the target email inbox.

In a specific instance, these emails are stuck in the Mail app’s outbox.

To check if the emails are stuck, open the Mail app, and go to the outbox. If there is a number next to it, that means emails are pending and are not being sent.

To try and resolve the problem, we strongly recommend removing and adding back the email account used for sending files on the device.

Please refer to Apple’s official instructions here on how to do so.