KrazyKid:

 

Can you try doing a credit card charge back for overcharging? Don't know it will work but worth a go.

 

I'd be claiming because I didn't receive the service ordered. 
(You paid for delivery of a large parcel but only received a small parcel.)

 

https://www.westpac.co.nz/help/how-to-dispute-a-credit-card-transaction/

 

https://www.consumer.org.nz/articles/credit-card-chargebacks  

 

They asked for my number but then still haven't heard from them so I let them know that I have opened a dispute through my credit card. 🤞