Modern Xiaomi smartphones running under the control of shells MIUI or new HyperOS, often equipped with two slots for SIM-But it's this functionality that sometimes causes confusion, especially when the device starts making calls from the wrong card, or refuses to make calls at all. Understanding the logic of the room selection system is critical for comfortable use of the device in everyday life.
Device owners are faced with a situation where, after updating the firmware or accidentally pressing, the settings are confused, and the priority SIM card changes. This can lead to unexpected costs if the call goes at a more expensive rate, or to skip an important conversation if the main SIM card was in the area of poor reception. In this article, we will discuss in detail how to force the desired SIM card for outgoing calls, how to set up automatic selection and what to do if the settings menu is not working correctly.
We will not only look at standard settings via menus, but also touch on specific features such as locking a second SIM card for calls or using voice assistants to manage calls. SIM-Management allows you to save budget and save nerves, eliminating the need to ask the interlocutor each time, which number to call him back.
Basic setting of priority SIM-call-card
The basic method of managing SIM cards on Xiaomi smartphones is focused on a single settings menu, which is available regardless of the version of the operating system. To change the default SIM card for outgoing calls, you need to go to the Settings section, then select the item SIM-And that's where the key switch is, which is the behavior of the phone when dialing.
In the menu that opens, you will see the Calls block, which displays the current selected card. Clicking on this item, the system will offer three options: Always Ask, SIM 1 or SIM 2. The Always Ask option is the safest option if you use both rates actively and do not want to risk the balance, in which case a pop-up with an offer to choose the operator will appear with each dial.
If you prefer automation, choose a specific SIM card (for example, one with unlimited minutes attached) and then all calls from the contact book and log will be made automatically through the selected slot. It is important to note that settings for MMS and mobile Internet are set separately in the blocks below, allowing you to keep the Internet on one card and voice communication on the other.
- 📱 Go to Settings. → SIM-Maps and mobile networks for access to management.
- 🔔 Choose the “Always Ask” option if you’re afraid to spend extra money on calls.
- 🚀 Install a fixed SIM card to speed up the dialing process.
- 💡 Remember to check the settings after each device restart if there are failures.
It is worth considering that some Xiaomi models may have a slightly modified interface depending on the regional firmware (Global, China, EEA).If you do not find the described items, use the search by settings, typing the request "SIM" or "Calls". The system will redirect you to the desired section, which is especially convenient on the large screens of flagship models.
Selecting a SIM card directly during dialing
Even if you have an automatic SIM card installed in the general settings, MIUI provides the ability to change this decision at the last minute, implemented through the dialing interface (caller), which is standard for most devices of the brand. When you open the Phone application and dial numbers, the indicator of the current selected SIM card is often displayed under the number field or next to the call button.
By clicking on this indicator (usually a small operator icon or a 1/2 number), you can instantly switch to another SIM card before making a call. This function works preventively: if you change the SIM card in the dial interface, the next call will be made from it, but this does not change the global default setting for all other calls.
⚠️ Note: If you accidentally chose the wrong SIM card and the call went, immediately terminate the call. In some tariff plans, even a second whistle can be regarded by the operator as the beginning of the connection and charge a fee per minute of conversation.
In addition, the call log also stores information about which card the call was made from. When re-typing from the history, the system usually suggests using the same card as the last time, which is convenient for feedback. However, if you called from a working SIM card, and you need to call back from a personal one, be sure to check the indicator before pressing the call button.
In newer versions of the HyperOS shell, the logic of the work has become even more intelligent: the system can analyze which number you called from earlier, and suggest calling back from the same SIM card. This behavior is customized in deep call parameters, but by default is often turned on for the convenience of users who do not want to get confused in the dialogue.
Configure calls for specific contacts
One of the most useful but little-known features is the ability to attach a particular SIM card to a specific contact, ideal for those who clearly separate personal and work communication, for example, you can set your phone so that your mom always calls from your home SIM card, and calls to your boss only from your corporate one.
To implement this scenario, open the Contacts app, select the right person, and click on the call or edit button. In some versions of MIUI, when you click on the call button in the contact card, the SIM card selection menu with the tick "Remember the choice for this contact" immediately appears. If this option is not available immediately, try to make the first call by selecting the desired SIM card, and the system will prompt you to remember this choice.
- 📞 Open your contact card in the Xiaomi phone book.
- ⚙️ Click on the call button and select the required SIM card from the list.
- ✅ Confirm the action so that the system remembers the preference for this subscriber.
- 🔄 You can change the binding at any time by repeating the selection procedure.
This flexibility avoids awkward situations where a business call leaves a personal number, or vice versa. It is worth noting that linking a SIM card to a contact takes precedence over the global settings of the phone. That is, even if you have to “Always ask”, the choice for fixed contacts may not be necessary if you previously ticked “Do not ask again”.
What to do if contact resets SIM card selection?
It’s also worth mentioning that when you sync your contacts with your Google or Mi Account, these settings may not be stored in the cloud. They’re stored locally on the device, so when you change your phone or reset to factory settings, you’ll have to manually restore the SIM card attachment to your contacts.
Using widgets and quick settings for management
For those who prefer to have visual control of the situation, Xiaomi offers handy desktop widgets «SIM-The card allows you to switch active SIM cards for calls and the Internet with a single touch, and turn them on or off completely, which is especially true in situations where you need to quickly switch to only one SIM card mode, for example, during a meeting or when roaming.
To add a widget, pinch the empty space on your desktop, select “Widgets” and find in the list «SIM-If you drag the widget onto the screen, you get quick access to toggles, and you can not only change the priority SIM card for calls, but you can also see the signal level and operator name for each slot.
| Control element | Function | Where to find out. | What's useful for? |
|---|---|---|---|
| Global tuning | Installation of the SIM card by default | Settings → SIM-map | Continuous use of one tariff |
| Desktop widget | Quick switching and disconnection | Desktops → Widgets | Operational management without entering the menu |
| Interface of the set | One-time choice before the call | Dialing screen | Situational calls from another number |
| Contact card | Linking the number to the subscriber | Annex Contacts | Automating calls to specific people |
In addition to widgets, you should pay attention to the notification curtain. In the extended menu of quick settings, there is often a “Flight Mode” switch or separate tooggles for the purpose of the new device. SIM-If you add a card to it, you can tap the SIM icon in the curtain and turn it off instantly, which is useful if you need to stop calling that number without removing the physical card.
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Add the widget. SIM-If you travel frequently or change fares, this will save time and avoid unnecessary roaming costs by quickly disabling an unnecessary SIM card with one tap.
Solving problems with the definition of the SIM card
Despite the system's cleverness, users sometimes encounter bugs when the phone ignores settings and calls from the wrong card, or does not see one of the SIM cards at all. Often the problem lies in a software failure of the communication module. The first step in such cases should be a banal but effective reboot of the device, which allows you to re-initialize the modem and re-read the configuration of the slots.
If the reboot didn't help, check if the "Call Lock" mode for a particular SIM card is activated. → SIM-maps and mobile networks → Settings SIM (or just clicking on the SIM card, you can check the box that prohibits outgoing calls, and make sure that the Call Barring section does not include any bans from the operator.
In rare cases, network resets help. This action will not delete your personal data (photos, contacts), but will return all network parameters to factory values, including APN access points and network preferences. The path to this feature: Settings → Connection and Sharing → Reset Wi-Fi, mobile networks and Bluetooth.
⚠️ Note: After resetting your network settings, you will have to re-enter passwords from Wi-Fi networks. Make sure to remember passwords from important access points before performing this operation.
If the problem persists, it may be a physical contact group or the problem itself. SIM-Try to remove the tray, wipe the SIM contacts with soft dry cloth and insert them into another slot. Sometimes it helps to replace the old SIM card with a new one in the operator’s cabin, since old Mini-SIM cards (cut) can not communicate well in modern thin smartphones.
☑️ Diagnosing problems with SIM
Features of work in Dual SIM and 5G mode
With the introduction of fifth-generation (5G) networks and improved communication standards, the MIUI shell has introduced new nuances of the two SIM cards. In some regions and on some models, activating 5G mode on one SIM card can automatically transfer the second SIM card to 2G/3G mode or even temporarily disable it if the modem does not support simultaneous operation of two active channels of the high-speed standard (DSDSDSDSDSDS – Dual SIM Dual Standby).
Users who are critically important to take calls to both SIM cards at the same time are advised to carefully monitor the indicators in the status bar. If the second SIM card lost a signal or appeared the inscription “No network” when actively using the Internet on the first, it may be worth switching the network type to LTE in the mobile network settings, this will ensure more stable operation of both channels.
Also worth mentioning is VoLTE (Voice over LTE) feature.If both carriers support this technology, you can talk on one SIM card in high quality while the second one remains available for incoming calls or the internet. On Xiaomi, VoLTE setting is usually enabled by default, but if you have problems choosing a SIM card during a conversation, check if that switch is activated in the SIM card menu.
Owners of the Black Shark or RedMagic series of gaming smartphones (which are often based on MIUI) may face an additional layer of control, a game mode, which can be configured to prioritize calls during the game, so as not to interrupt the process, or completely block incoming calls, except for selected contacts.
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The stability of the two SIM cards depends on the support of communication standards by your operator and the chosen modem model in the smartphone. When frequent failures, switching to 4G Only mode often solves the problem of choosing a SIM card.