Why suddenly the pricing was changed?

I recently received this email.  I am signed up at the storage rate of $5 per month.  The next one is $19.95.  However, we have never paid more than $9.95 per month?  Can you please advise?

Dear WCAA2012,

You have currently reached the limits of your account. Your forms are disabled now.

Upgrade your account today to continue using JotForm; receive submissions, collect payments from your users and have more upload space. Upgrading is quick and easy:
https://www.jotform.com/upgrade?username=WCAA2012

Thanks for using JotForm,

JotForm Team
http://www.jotform.com/ 

We apologize for the inconvenience.

The pricing was changed and what you see in the updated pricing for Bronze plan. You can check the latest pricing in our pricing page at https://www.jotform.com/pricing.

Let us know if you have any questions.