Touch ID iPhone 6 not work

I live in Brazil and I bought an Iphone 6, in the Apple store on Fifth Avenue in New York in April 2015, now discovered that the "touch id" does not work when I try to use it gives the following message: "Could not complete the configuration of Touch ID. Please come back and try again ". I took the phone at an Apple store in Brazil and they informed me that it is a physical defect, but the phone is "A1586" model, this model is not approved by Anatel, the approved type is the "A1549". I wonder if I take the phone at the same store I bought it is possible to exchange it for another phone, preferably the type approved in Brazil?