How does Unicom change the traffic package?

you can change all the existing packages in the local business hall, or you can log in to the online lobby or change the customer service. However, the packages changed by the general customer service and online lobby are limited, and not all packages can be changed. If the net hall and customer service don't want to change the package, they can only bring the valid certificate of the owner to the business hall where they belong to change the package.