How to open Unicom's night traffic package?

Some provinces of China Unicom have introduced free traffic package service, but the tariffs in different provinces and cities are different. According to different provinces and the package you use, the opening method is different. If you are a Guangdong user, you have the 5 yuan Package1.5g "3G Play" free traffic package, and the free time is 00: 00-9: 00, and the excess will be charged according to the original package tariff. If you are a user in other cities, it is recommended to consult Unicom customer service for details.