07-04-2012 08:01 AM
Hello NatMel and welcome to the BlackBerry® Support Community Forums.
Sorry to hear you are having SMS issues.
Did you backup your personal data recently? If not, then once a message is deleted it not possible to retrieve it.
If you need to save important messages, including SMS, on the message you can go to Menu>Save and it will be stored to your "Saved Messages" folder, even if you delete it from the main messages folder.
Your Saved Messages folder may be hidden. To check go to Menu>Show All on your home screen.
Hope this answers your question.