Why Xiaomi turns off the Internet when calling – all the reasons and solutions

Have you noticed that your Xiaomi phone suddenly disappears when you call in or out? This problem is common for many users of the brand, from budget Redmi to flagship Mi and POCO. In some cases, communication is restored after a few seconds, and sometimes the Internet remains disconnected until the device is rebooted or manually reconnected.

The reasons for this behavior can be both software (firmware errors, configuration conflict) and hardware (problems with the communication module or SIM-In this article, we will discuss the 7 main reasons why Xiaomi loses Internet during calls, and give step-by-step instructions for their elimination.

Importantly, if the problem occurred after the MIUI update, try rolling back the firmware version or resetting the network settings first, which helps 60 percent of the time.

1. Conflict between VoLTE and 4G (most common cause)

Most modern Xiaomi supports VoLTE (voice over 4G), but its work is not always stable. When VoLTE is activated, the smartphone switches from LTE to VoLTE during a call, and if this process is error-prone, the Internet can shut down, especially on models with MediaTek processors (for example, Redmi Note 11 or POCO X3 Pro).

How to check:

• 📱 Open the Settings. → SIM-maps and mobile networks → [Yours. SIM] → Enable VoLTE.
• 🔄 If the option is active, turn it off and check if the Internet is still on the phone.
• 📡 If VoLTE is disabled but the problem remains, try turning it on (sometimes forced activation helps).

On some firmware, MIUI VoLTE can automatically shut down after an update, and conflict occurs if the operator does not support this technology (for example, some virtual operators).

2. Errors in APN settings (access points)

Wrong parameters APN (Access Point Names can cause your phone to lose contact with the carrier’s network when you call, especially if you’ve recently changed handsets. SIM-map, updated firmware or reset settings.

How to fix it:

1. Go to Settings. → SIM-maps and mobile networks → [Yours. SIM] → Access points (APN).
2. Click on the three dots in the top right corner and select Reset to default values.
3. If this doesn’t work, create a new APN manually (options can be requested from the operator or found on its website).

Note the APN type fields, which should indicate default, supl,mms (for most carriers), and if it only says default, the Internet can be turned off when you call.

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Before resetting the APN, save your current settings – take a picture of the screen or write down the settings in a notebook.

3.Problems with SIM-card-slot

If the Internet is only disabled when using a specific SIM-The problem may be in the card itself or the slot:

• 🔧 Damaged or scratched SIM-cards (especially if the contacts are oxidized).
• 📶 Virtual operators (e.g. Tele2, Yota, SberMobail) that work through the networks of other providers.
• 🔄 Two. SIM-map-to-card DSDS (Dual SIM Dual Standby, when one of them shuts down the Internet when the other is active.

How to diagnose:

1. Try inserting. SIM-card to another slot (if you have Xiaomi with two slots).
2. Test the card on another phone.
3. If you use two SIM-Disable the second card and check if the problem persists.

On some models (such as the Redmi 9A or POCO M3), the second slot can be combined with a microSD slot. If you use a memory card, try removing it - sometimes this solves the problem.

4. software bugs in MIUI (especially after updates)

MIUI is known for its frequent updates, but not all of them are tested on all models. If the problem occurred after installing a new firmware version, it is most likely a system bug.

• 📱 MIUI 12.5 and MIUI 13 on older smartphones (e.g. Redmi Note 8 Pro).
• 🔄 Beta versions of firmware (if you are a member of the Mi Pilot program).
• 📡 Firmware for Global Versions (Global) ROM), Chinese-designed.

Decisions:

• 🔄 Reverse to the previous version MIUI through settings → The phone. → Updating the system → Three points. → Select a Service Package.
• 📱 Reset network settings: Settings → System system → Resetting settings → Resetting Wi-Fi, Mobile Network and Bluetooth.
• 🔧 Install custom recovery (for example, TWRP) And run a clean version of the firmware.

On some models (e.g. Xiaomi Mi 10T), the bug with the Internet shutdown when calling was officially confirmed and fixed in MIUI 12.5.4.

Hardware malfunctions (communication module or antenna)

If none of the software methods helped, the problem could be in the hardware:

• 📡 Damage to the antenna module (for example, after falling or getting moisture).
• 🔌 Failure of the modem (chip responsible for mobile communication).
• 🔋 Power problems of the communication module (for example, bloated capacitors on the board).

How to check:

1. Call from your smartphone to another number and check the signal level (if it constantly “jumps” or shows 0 dBm – this is a sign of a malfunction of the antenna).
2. Connect to Wi-Fi and check if the Internet is stable, and if so, the problem is definitely with the mobile module.
3. Try inserting. SIM-If everything works there, it's a malfunction in your Xiaomi.

The most vulnerable to such problems are models with a metal body (for example, Xiaomi Mi 9 or Mi 11), where antennas are located at the edges and can be damaged when impacted.

⚠️ Warning: If your smartphone falls or gets wet, don’t try to disassemble it yourself – this can lead to a short circuit.

6. conflict with applications (especially SEOs and VPNs)

Some apps can block mobile traffic during calls, most often to blame:

• 🔒 VPN-Clients (e.g. NordVPN, ProtonVPN) that intercept network traffic.
• 📱 Battery optimizers (e.g. Greenify, AccuBattery) aggressively restrict background processes.
• 🔄 Applications to speed up the Internet (for example, Internet Speed Master).

How to find the culprit:

1. Run your phone in Safe Mode (press the power button → Safe Mode) If the problem has disappeared, the third-party app is to blame.
2. Turn off applications that may affect the network and check the connection.
3. Check application permissions in Settings → Applications → Permissions Management → Autostart and Battery Consumption.

For example, Greenify can default to freezing system processes that run mobile communications, and some VPNs block traffic when switching between 4G and 3G during a call.

7.Problems on the operator side (regional restrictions)

Sometimes the problem isn't with the phone, it's with the operator's settings.

• 📡 Concurrent voice and data transmission restrictions (occurring in small operators).
• 🔄 Wrong binding IMSI to the service profile (for example, if you have recently moved the number to another operator).
• 📱 Regional restrictions (for example, in roaming, some operators turn off the Internet during calls).

How to check:

1. Call the operator support and check if simultaneous voice and data transmission (SV-LTE) is supported.
2. Try inserting. SIM-card of another operator (for example, MTS instead of Beeline).
3. If you're roaming, turn it off and check the connection.

Tele2, for example, had a problem with internet shutdowns on some fares until 2022, and MegaFon had similar complaints from subscribers with All Inclusive rates.

⚠️ Warning: If the operator says they're fine, but the problem persists, ask for a diagnosis of your line. Sometimes errors occur due to improper attachment of the number to the equipment.

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Before contacting the operator, check the phone on another device or with another. SIM-map - this will help to more accurately identify the culprit of the problem.

What do you do if nothing helps?

If you’ve tried all the ways, but the Internet on Xiaomi still shuts down when calling, there are radical measures:

• 🔄 Reset to factory settings (don't forget to back up!). Way: Settings → System system → Resetting settings → Delete all data.
• 📱 Fastboot flashing (if you are confident in your skills) will require Mi Flash Tool and official firmware.
• 🔧 Contact a service center (if you suspect a hardware malfunction) and Xiaomi has official partner centers in most major cities.

Before resetting or flashing, check whether your model is not covered by the warranty. If so, you should contact the service immediately, so as not to lose warranty service.

It's also worth checking if your problem is massive.

1. Look for complaints on forums (e.g. 4PDA or Mi Community).
2. Check if there is an update that fixes the bug (in Settings → About Phone → System Update).

Check out VoLTE|Update firmware|Reset the network settings|Test the other one. SIM-map|Calling for support for Xiaomi-->

FAQ: Frequent questions about the problem