Goods not delivered

On the 23rd of October 2019 I placed an order with LN Poultry Holdings for 16 goats and they were meant to be delivered on Tuesday the 29th of October 2019. However, my order was not delivered and I called the people who were in charge of the delivery. They then told me the order would be delivered on Wednesday. On Wednesday when I called I was told that one of the goats was pregnant and it had given birth. I was then told to send more money for the kids.

The issue now is that they want me to pay R15000 yet I've already paid R8000 for the stock and R7000 for insurance. The insurance money is refundable after delivery is successful.

I have been calling LN poultry holdings and the transportation people and they're not giving me a reason as to why I should pay R15000.

I now feel like I'm being ****med, hence I'm seeking help.