I found these fare rules on Expert Flyer for CZ I class - cancellation $450. You would need to check the fare basis is exactly the same.
Rules
Search: Departing CHC on 17/04/19 for CDG
Fare basis code IZQNB
Flying CZ
PENALTIES FARE RULE
CHANGES, ANY TIME CHARGE NZD 150.00.
CANCELLATIONS, BEFORE DEPARTURE CHARGE NZD 450.00.