Garmin Pay and ASB Bank (New Zealand). Has anyone managed to set their watch up?

So I went through the procedure via the Connect app (on iOS) and everything is pretty easy, but when it comes time to register my card it comes back with an authorization error telling me to get in touch with my bank. ASB tell me there's nothing wrong on their side so they say it's a Garmin problem. Pretty annoying.
So before I start the arduous task of contacting Garmin to remedy this - has anyone else in NZ had any luck registering their ASB Visa card for Garmin Pay?