coupon code not working

Input the coupon code for free shipping on my site, but at checkout when you enter the code and hit update the shipping remains.

Process:
Entered coupon code name KRS0710, selected free shipping from drop down, start date of the 12th end date the 30th, use once unselected, active checked, all products checked, property subtotal_amount, logic equal, value 75.00.

Can anyone see what Im not doing here?

thanks,
alex