In a logical move, Google has announced that they have cancelled their prepaid cards in Google Wallet. Considering that any bank card now works with Wallet, there isn’t any point in it anymore. While it is a logical move, only time will tell if it is a good one.
After September 17th, you will not be able to add any balance to a prepaid card. After this announcement, we wouldn’t suggest you do so at all. And after October 17th, your card will be gone. You have until then to spend the rest of the balance. Luckily, you can split your purchase, meaning you can buy something more expensive than your balance, use all that money, and pay the rest with a different form of payment at most stores. Means you don’t have to buy something costing the exact amount of money on your card.
If that still doesn’t satisfy you, you can also ask for a refund. The refund will take 8 weeks, but you won’t have to worry about losing any money. I think this is a wise decision, since no one loses anything.