Refunding payment after delaying of delivery goods

In 2023, supplier sent photos and emails to the Northern European buyer, for quota of the electric car, with the delivery terms, 40 electric cars, started production in 10 days after receiving the deposits, and deliver the cars after receiving the balance in fifteen days. And the supplier will test all the cars before shipping. After the buyer paid the supplier, the supplier did not deliver the cars on time. So buyer requested the supplier to refund the payments. But the supplier refused to refund and claimed they had already paid their factory for these cars. So the dispute occurred. After we accepted this case, on behalf of buyer, we sent letter to supplier and demanded them to refund the payments with compensations. Because buyer can not get profits for the failing of this business, buyer has loses. After several negotiations with the supplier, at last, the supplier returned back all payments with reasonable loses to our client. And our client is satisfied with the result of the settlement, and has more confident with the Chinese trade business.