Whether you are trying to make a Spaceships booking and pay the deposit or wanting to pay the remaining balance, a declined payment can happen for various reasons. The most common reason is that your bank is blocking it due to the fact it is a higher amount you usually spend, there isn't enough money or spending limit on your card or the currency of the payment (NZD) is a currency you usually don't make payments in.
Banks have all kinds of security rules & systems in place to protect you, the customer. However, it can annoying for you as traveller when trying to pay the (remaining) balance of your booking. So here are some tips and/or info what to do it it happens:
Debit cards get blocked more often by the security systems of a bank than credit cards. If your debit card doesn't work, try using a credit card.
The Spaceships Secure Payment System allows you to split the payment into several smaller payments as you can set the amount you would like to pay. As long as you make sure it's at least 20% when paying the deposit and 100% of the booking amount when paying the remaining balance. The system will show you how much is due and allows you to set the amount you would like to pay. Then repeat it to make another payment.
Use a different card, for example one that is in the name of your travel companion or a family member.
When the issue continues, please contact your bank as they will have more details about why they blocked the payment and how to fix it or get around it.