1. Traffic data consumption statistics are delayed. Generally, the mobile traffic statistics of the three major operators are not real-time, but there is a certain time delay, ranging from ten minutes to several hours. So sometimes users will find that even if the mobile phone traffic is turned off, they will receive a reminder message with excessive traffic. This is because after the data function is turned off, some traffic is counted by operators.
2. Some system functions have reopened traffic data. Under normal circumstances, the mobile phone will automatically use the wireless network in the WiFi environment, instead of using the traffic network. However, in order to ensure the normal network, some mobile phone systems also support the simultaneous use of WiFi and traffic. For example, Apple has added the "WiFi Assistant" function to iOS 9, which can enable traffic when the quality of WiFi is poor, and help users get a better network experience. Later, Huawei, OPPO and other domestic mobile phones also added similar functions. However, after this function is turned on, it may also consume traffic in the WiFi environment, so it is best for users with little traffic to turn off this function.
3, the system has bugs stealing traffic. Generally speaking, third-party apps can't break through the system authority to open the traffic function, so mobile phone stealing traffic is mostly caused by the system itself. For example, functions such as album cloud backup are started on the premise of turning off traffic, which leads to traffic stealing. Either the mobile phone ROOT or some third-party apps have higher permissions after jailbreaking, and can automatically turn on the traffic function without the user's knowledge. You can use the mobile phone's own traffic statistics function to see which system functions or third-party apps continue to consume traffic after turning off traffic.
4. The background of the operator is wrong. It is not impossible for operators to make mistakes in background traffic statistics, resulting in continuous consumption of user traffic. Many users reported that when traveling abroad, the traffic function was obviously turned off, but the mobile phone stole thousands of bytes of international traffic. Although it costs less, it is also annoying. However, in this case, it is difficult for users to prove that it is the operator's problem, and it is generally gone.