What is the failure of China Mobile's "SMS sending" prompt? Invite professionals to participate.

This alert tone indicates that the phone will transfer the number to a special voice platform, otherwise the normal alert tone will not be like this.

Generally, this platform can only be owned by SP or people who have other business dealings with telecom operators. In most cases, it is a test platform, not a normal business use.

In any case, it is the fault of the mobile company that the calling party is charged without calling. They should apologize, punish employees, and compensate the transportation expenses and lost time expenses caused by complaints (Beijing has special laws and regulations to regulate such expenses, and the standard is calculated with reference to the personal income of the Statistics Bureau in the previous year).