I heard that there is a twin-city service. I wonder what this is.

Shuangchengtong refers to the service that users use 1 UIM card, have two mobile user numbers and can communicate based on the two mobile user numbers. One of the mobile subscriber numbers is called Master Number (MDNa) and the other is called Virtual Number (MDNb), which are managed and allocated by China Telecom. The Tianyi number of the user's UIM card issuing place is called the main number in this business, and the user's business acceptance and charging can only be realized through the main number. When receiving services from two cities, the added number is called a virtual number, which can not handle any business alone or stop to answer the phone, and is only used for voice and SMS calls. At present, Guizhou Shuangchengtong service only supports the virtual number service in which Guizhou main number is bound to other provinces. International, Hong Kong, Macao and Taiwan regions can not be used as virtual number attribution to open twin-city services. Customer service 46 will answer your questions. Broadband service can self-help troubleshooting, which is simple and easy to operate. In addition, you can also handle work order inquiry, ITV troubleshooting, broadband application and password service, which is convenient and fast. For more functions, please pay attention to China Telecom's Guizhou customer service.