After receiving the short message, Alipay said that Liu Yuhan had paid for me, and there was a transaction number for receiving and paying at any time. What do you mean?

Did you find someone to pay online, and then when you receive the goods, you can confirm the payment when you get the goods. You must get the goods before payment. The transaction number is the transaction number for buying things.

Nothing else. You don't know that you bought something and found someone to pay for it, do you?