Why Does My iPhone 6 Keeps Saying " The Message Could Not Be Moved To The Mailbox Trash"? Here's The Reason Why.
When this happens, the first step is to force-close the app and restart the device. If that doesn’t work, we have found that removing the mail account from the app and adding it back will fix this issue. It’s usually a server problem connecting with the mail account and is probably the reason why the server can’t talk right