The MMI code in the phone is the code that ensures the connection between the operator and the user during UUSD requests. It is MMI that generates user queries. How to get rid of an error with MMI and what could be the reason for such a malfunction?
MMI features and functions
MMI, or Man-Machine Interface, is a man-machine interface that starts working when checking balance, replenishing an account, connecting to any services, as well as when changing tariff plans and other similar operations.
The MMI function code begins as usual for each user - with an asterisk, and ends with a hash symbol. Between two characters there are numbers or numbers with symbols, and each such code performs a certain function useful to the user. Therefore, it is important to know what to do if the MMI codes suddenly stop working.
Reasons for the error
In some cases, instead of answering the request, the user sees an inscription stating that he entered the wrong MMI code on the phone. And the first thing to check in this case is the nature of the problem. Very often, failures are accompanied by certain messages in the spirit of "invalid code", "connection error" or simply "incorrect MMI code". Sometimes the message disappears unexpectedly and disappears unexpectedly. And it can appear for the following reasons:
- Incorrect operation of 4G and 3G networks during technical and repair work.
- Physically worn out SIM card. However, in this case, an error will appear both during USSD requests and when performing other functions.
- Problems in the mobile device and its settings.
- In rare cases - negative impact of applications.
An important point: most often problems are associated with 3G and 4G networks.
How to fix the problem
In order to quickly get rid of the problem with the MMI, you can try the following steps:
- Go to the settings of your phone and mobile network.
- Temporarily switch from 4G to slower.
- Switch on the airplane mode of the phone for a while and return to the classic mode.
- Switch to the original network and reboot the device.
In the event that after performing these actions and returning the settings, the problem with MMI has not disappeared, you should try to make any request on lower-level networks (for example, it can be a request in 2G networks). After a while, the problem should be resolved.
General solution for operators
The general scheme of actions looks like this:
- restart the device;
- go to settings;
- switch to a lower network, that is, 2G or 3G;
- go to the settings item "network operators";
- check your phone settings for any failures;
- switch to your operator.
Exactly the same actions must be performed for any other operator. However, users note that simple methods such as turning on "Airplane", switching the network rank and rebooting the device help most often.
