When using the parking kiosks downtown you should always check if your stall number has any time left on it before purchasing your parking. The person before you may have left early and you can use that time if any is available. After waking the machine up and selecting English/Spanish:

1. Enter your parking stall number.
2. Select 2) Add Time on the menu.
3. Time remaining (if any) will be displayed.
4. Now you can pay for more time if needed.

If there’s no time remaining you will be taken back to the select language option (because the machine can’t remember that far back, apparently) and you can then purchase your time.

If you just choose 1) Purchase Ticket every time you may be missing out on some free minutes.