Need to cancel a sale buyer's address is not valid

[bradymarm]

Hi,

The buyer of an item of mine wants me to change the shipping address and if I do so I will not be protected.  It is to an FPO and in my item description I stated that I cant ship to that.  The buyer changed his address to pay for the item.  When I went in to print the label it said invalid address and that I would not be protected by e-bay if I changed it, and the item is expensive.  So I need to cancel the sale but it wont let me because the item had been sent to the resution center for an un paid item case.  Should I call e-bay for help?

Thank you,

bradymarm