I did not use the up the amount of time I paid for. Why am I being asked to pay again?

Timed access for websites starts when you add the item to your tab and runs until the end of the time purchased. Leaving the website does not stop the timed access.  For instance, if you pay for 24 hours, your access will last until the next day. Access does not last until you have used the website for an accumulated 24 hours.