Do the measured diameters of the new rotors match the ones you removed?
Are you 100% sure the correct rotors were inside the box? I ordered EBC rotors online from another vendor and they were drop-shipped direct from EBC. TWICE I got the wrong rotors inside the box (box part number was correct, but the rotors inside were wrong). In my instance, the rotors were the right dimensions, but they sent the slotted-only rotors instead of the GD Sport (slotted and dimpled).
EBC finally got it right on the third try, but it took over 2 weeks to get it all sorted once I discovered the issue.
EDIT: Just saw your second post. I assume your new rotors also measure 13.3in, in which case they are likely not compatible without the proper upgrades. :/