Before September 2023, when the Chinese Yuan was still a hard currency, a classmate asked me in advance about getting married. At that time, the market price was 400-410. I said, why not stock up now, I can give you 400 now; otherwise, the price will definitely go up during the New Year, and it will be hard to find. He said it was fine, just let him know when the time comes. A week before his wedding, he asked me for 30 pieces, and not from outside. I said, you want that many? I only have ten now, and I have to go find prices at other places for 420. He said okay, once I find enough, let me send it to him, saying he was waiting for a gift package, with a round trip of 100 kilometers. I said fine, after I delivered it, he initially said he wouldn't pay me right away. I said all this money was advanced by me, then he said didn’t we say it was 400 in the summer? I said the price back then is different from now, and then he said the price we agreed on was reasonable because I was in a hurry to use it, and it was hard to buy temporarily, so the price went up. Anyway, he had all sorts of excuses, and in the end, I said: fine, give me 400. After the payment was completed, I didn’t attend his wedding and sent a gift with other classmates. A few days later, he said the unused Yuan needed to be returned to me. I said it belongs to my family, I can take it back, but I can't help you return it to other places. After that, I no longer had contact with this classmate.