Cart Value shows as NIL but Checkout value correct

I have been using your plugin for maybe a year without issue. I have just noticed an issue which may be new or it may have been there all the time. After a product with custom price is added to the cart, it appears in the cart with NIL value. If you then go to the Checkout the value appears properly. Is this a bug or do you know a fix? You can see this by using the link https://www.presentsofmind.com.au/game/special-order/

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