left to pay – not working

I put in “Deposit Settings” that you have to pay $500 in each product.
But when you go to payment it said “left to pay” $500 also, and thats not the correct amount. Also it doesn´t change the amount when you change the selection of the products, always says $500 letf to pay and have to pay. And my products are not $1000.
Thnaks

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