I’ve seen a few people having trouble with this lately so thought i’d post here in case it helps anyone.
When I bought my iPhone 13 Pro last year I lost my esim when setting up the new device. Contacting Spark fro assistance was met with a lot of requests to come into a store to have a new esim issued. This is a huge problem as I am not in NZ at the moment and visiting a store is not possible.
After some back and fourth I was finally directed by someone to a roaming support number which were able to ID me with information associated with my account and email me a new esim.
I was told to give the roaming team a call on +800 4663 2460. This is a free call from a landline when you’re in Australia. Alternatively, you can call +64 3 371 0866. This is a free call from a Spark mobile.
I think the first number would be inaccessible from Australia and calling the +64 3 371 0866 number would be available from any mobile or landline in Australia or internationally.