Have you tried the cards in more than one location? ATM machine as well as point-of-sale debit? If so, it could be that your debit cards got de-magnetized and so the information contained on the card (your name/account number) cannot be read by the machine you are trying to use. This can happen on occasion with any card that has the magnetic information strip on the back of it.
Another possible reason that your cards do not work is there may be a block on your account. Some financial institutions block the account in case of suspected illegal activity, in case of death of a spouse who is named jointly on the account, or other reasons.
You should contact Customer Service for your debit card. The phone number should be on the back of the card. Explain that neither of your debit cards work, and ask them if there has been a block put on your bank account or your cards. If there has not been a block, you will probably have to ask them to issue new cards for each you and your husband. This may take some time, so be prepared to write some checks for a little while, or go in person to a bank to withdraw some cash until you get your new debit cards.
Good luck to you!