For the Gmail Messages Are Missing, log into your Gmail account and click on the "Trash" folder. If the messages are there, you can move them back to your inbox by selecting them and clicking on the "Move to Inbox" icon.
Log into your Gmail account and click on the "All Mail" label. If the messages are there, select them and click "Move to Inbox."
Messages not in Trash or All Mail may be permanently deleted. Contact Gmail support to see if they can recover the messages.