Upgraded for 50% discount, it wasn't applied?

How do I use the upgrade discount? I clicked on the "Save 50%" to upgrade and it still used the normal pricing for the Silver plan. I wanted to do the Silver Plan at $19.50/month...Please advise. thanks! 

The discount is only available for yearly subscriptions.  The pricing shown is 50% off what monthly would be, but billed annually.  If you'd like, we can cancel your current Silver subscription and you could then upgrade to the discounted yearly subscription of your choosing.

That makes sense. Thank you. I'll take care of it. Have a great day.