How to open the boot reminder service?

"Power-on reminder service" is a call reminder service for China Telecom Tianyi calling users.

When the user's voice call fails (because the called user is turned off or not in the service area), the service of providing the calling user with the information of the called user's power-on is provided. That is, the user who has customized the startup reminder service is the calling party calling the called Tianyi user. When the called party cannot be connected because the called party is in the disconnected state, the startup reminding service platform will inform the calling party and the called party of the startup information in time through short messages.