The website has caching issues. Maybe try to clear cache first, incognito mode or a different web browser. Or try on a different device. Sometimes if you try too often on one credit card, it will be "locked" out for about 24 hours. You could try a different credit card if possible.
try dialing 611 to hear current plan status and to make a renewal payment. You will need to know your Public Mobile pin number.
added..alternative is to start process of contacting Customer Support by clicking the orange bubble on lower right side of the page...if that fails, use this link instead...
