The deposit is non-refundable, because you chose to order their goods, and then you chose not to buy them, which formed your liability for unilateral breach of contract. So, in the case of your first breach of contract, you don't want to refund the deposit to the mall. Actually, you can do this. The price difference between the two shopping malls is only one in 500 yuan, and both are between 4.5-4 fold. Because both of them are 4.5% off, the two add up to only 10% off the original price. If you like, you can buy a 1 diamond ring in each of the above two shopping malls, which will not only keep your deposit (that is, if you don't buy it, you will lose your deposit, and if you buy it, you will lose your deposit.