I'm going to be the bearer of unfortunate news.
If you're saying that you've signed in to your TalkTalk Mailbox and selected the Inbox and then Delete all messages function what I would say is that you can recover the Inbox by restoring those mail messages from the Trash folder.
But if you've also emptied the Trash folder with the Empty Trash function all I can say is that there is a warning message:
The reason for the question 'Do you really want to empty folder "Trash"?' is because this is a permanent deletion of the mail messages. There is no recovery for this action.
TalkTalk do advise that you back up important mail messages because there is no back up service offered by the Mail platform.
The mail apps on phone and laptop are set up as IMAP accounts and they don't necessarily back up mail messages locally and just mirror what's in the online mailbox.
The user would normally set an option to download mail messages for offline use and or save mail messages to local folders so that there is a local copy on the device. It's also then advisable to run a regular backup of that device to overcome any loss or failure of the device.
