You can either use the ez-link app or https://customer.ezlink.com.sg/Custo...k-Card-Expiry/ to check whether the card has expired (use the CAN # on the back of the card). If it's not expired, you should still be able to use it. If it has already expired you can go to a ticket office to get the remaining value refunded but they may charge you a few bucks for a new card.