Dependant Fields Not Removing

Hi,

I am building a quote request form, everything is populating ok, until I need to change my choices. IT doesn’t remove the previously selected choices.

Example:
I select racking as the first choice and it brings up a list of options, I then select New, this then brings up another list of options I pick 50-100m, then I decide I don’t want racking I actually want property maintenance and I select that up on the first drop down – instead of removing all the choices of population it gave for racking though and bringing up just the drop down choice for property maintenance – it brings up both. So for example property maintenance should not be showing the drop down for space and location description, it should only show the drop down with facilities management etc then once an item is selected there it should show priorities and timeframe boxes.

How do I trigger it to remove the previously selected options if someone changes their mind halfway through?

http://www.sunst8.com.au/quote-test/

The page I need help with: [log in to see the link]