That is sad to hear, but nothing that can be done against it. A question though, the 3C NFC's casing was made the same as the regular USB-A variant, but how will the USB-C go into phones with cases, now that it is now unlikely going to fit. To elaborate what I mean, the YubiKey 5C NFC has the main part and then a thinner part, to which the USB-C plug is attached, making it possible to actually plug it in, even with larger phone cases. I can understand that the casing had to be changed if it did not meet your requirements for being physically strong enough against breakage and tampering, but this issue made it unfeasible for me to get the 3C at all now (To which I'm unsure as to how to proceed since getting the 3A with a A-to-C converter permanently attached to it should not be the intended usage (nor does it look good visually, plus the attached converter could get lost in such a case)