You would need to contact the bank that handles the prepaid Visa Card. See the following
How do I report my card lost or stolen?
If you lose your card or believe it to be stolen, click here to report it lost/stolen. We will cancel your current card, transfer the remaining balance to a new card, and then mail it out to you at the address on file. A lost/stolen card replacement fee applies. See your Cardholder Agreement for more information.