Why is the express delivery in Jilin City so slow in December?

Express delivery in Jilin City in December was much slower because couriers were more sick. Jilin City, also known as Jiangcheng in the North Country, is a prefecture-level city under the jurisdiction of Jilin Province. It is an important industrial city in China approved by the State Council, an important central city and new industrial base in Jilin Province, and a tourist city with northern Chinese characteristics. It is located in Northeast China, Jilin In the central part of the province, it is the only city in the country with the same name as a province and city. It is an important transportation hub in Northeast China and Jilin Province, and a larger city approved by the State Council.