Restore a conversation in messages I accidentally deleted a conversation just now in Messages on iPhone. Is there anyway to undo this action or restore the deleted conversation in iOS 11?

The conversation still exists on my iPad but I would like to have the full conversation on my iPhone too.
Well, there is no real way of restoring it with one click. You could restore your iPhone with the latest backup file. So if you backed up your phone after you had that conversation, you could restore that back up, and you would have your conversation back. However, if you added any new things to your iPhone after your latest backup, they will be erased.