Form Calculations: calculation is not performed when selecting and deselecting the options.

We have a form for booth registration on our website.  When a user fills out the form by selecting a "booth", a calculation is put in the total field at the bottom.  Based on if they are a chamber member (yes or no), the price changes. 

However, if they fill out that they are indeed a chamber member and decide on changing their booth selection to a different booth, the calculation in the total field shows 0 instead of updating itself.  Is there a way to fix this?

 Anyone have any thoughts on this?  Is there a way to refresh the products after you re-select a booth?

It appears to be working fine, here is what I have tested:

So, the calculation was performed even after changing the Chamber Member option, and a different "Booth" option.