Unless something's changed in the past couple of weeks, you can't actually purchase more time for your topup card on the website. You have to go to the UTS store or the Mailbox in SXM to do that. Tim just posted that the UTS store near IZI has closed; does anyone know if there's another one on the island?

What you can do on the website is add time to your phone from your card, which you have to do every 90 days to keep your sim card, and therefore your phone number, active.