Default AT&T HTC One on Vodaphone in NZ

I'm from the US and am in New Zealand for a month. I own an HTC One which I purchased from AT&T and have been using on their network in the States. I've unlocked the phone, and also have S-Off. I've purchased a prepaid SIM card from Vodaphone in New Zealand. When I insert the SIM card, the phone asks me for the 8 digit SIM unlock code, so I entered the 8 digit PUK code provided by Vodaphone with the SIM. The phone tells me this code is invalid. I'm not quite sure why this isn't working - is it possible I need to load a different firmware to use the phone in New Zealand?

Kernel is 3.4.10-g31f7883
Firmware looks like 3.62.401.1

I'm currently using ViperOne ROM.

Certainly appreciate any input on this issue.

Thanks,
Josh