Sometimes, a message saying “Connection problem or invalid MMI code” shows up and can be frustrating for Android users. When the invalid MMI code message appears, it generally means that you can’t make calls or text messages until the issue gets resolved.
Fortunately, there are several ways to potentially fix the Android “Connection problem or invalid MMI code” error. Try the following options below. If one process fails to resolve the problem, move on to the next one.
There are several reasons why the “Connection problem or invalid MMI code” error message appears on your phone. The main reason is an issue with the carrier provider or problems with the SIM authentication on the smartphone. The error is quite common for phones with dual-SIM capabilities, but it does occur on others too.
Several different methods exist to fix the “Connection problem or invalid MMI code” on an Android device.
The first way to try to fix an invalid MMI code would be to restart the smartphone.
Another way to fix the Connection Problem or Invalid MMI Code on an Android smartphone would be to add a comma at the end of the Prefix code. When a comma gets added, it forces the operation to execute and overlook any error.
Below are two different ways to modify the prefix code.
The steps to access your network settings will differ, but the concept is the same. Follow along to check your network settings.
In closing, there are a few methods/options you can take to remedy the MMI error on your phone, some a little more involved than the others. While most MMI errors occur on dual-SIM phones, it also appears on phones with one SIM due to weak signals or tower network issues. If the above solutions don’t work for you, contact your service provider for assistance.