According to the inquiry in Zhihu, it is forbidden to resell goods without paying customs duties, which means that goods that have not gone through customs tax payment procedures are not allowed to be sold without permission. Goods that have not paid customs duties are generally sold by duty-free shops in special supervision areas of a country's customs. Because the goods have not paid customs duties, they are marked.
Reselling refers to selling an item at a high price at a specific time without the permission of the relevant department.