So in the last week I've noticed a significant uptick in missed calls from 021 numbers, that don't leave voicemails nor answer if you return their call. These calls used to originate from "No Caller ID" and foreign numbers (eg. Australia, the Phillipines etc).

I've answered a few of them to discover they are investment cold calls and scams. Each time, hanging up as soon as they identify where they're from.

As they are using New Zealand Mobile numbers, my question is whether there is a governing body or an email address where this abuse can be reported?

I assume they are registering these lines using the 'unlimited' mobile plans, or some sort of VOIP agreement and so I want to be able to report the phone numbers used to the provider for investigation.

Any ideas?