My own abilities. In this case, I actually think it is because of the merchant's own mistakes. When dealing with some things, I didn't find out clearly and didn't give some reasonable explanations. Then I guess I can't get it back. In this case, I shouldn't return the goods for the sake of our store's reputation. This kind of thing is the merchant's own fault, so the loss caused by this last mistake should be borne by the merchant. In this case, I can only face my own loss. This represents the ability of a shop and the ability to handle things.
We can negotiate. In fact, I think if this happens, then we should use the simplest way. Everyone should communicate, then coordinate with each other and reach an agreement. Then we can ask the user to refund or make up the difference through negotiation. This is the simplest way to deal with it. In this case, we can only minimize our losses and make up for our mistakes in this way, but unfounded returns are impossible. Everyone wants a chance to save money, so for many people,