Xiaomi Mobile Data Randomly Disconnects Throughout the Day

Xiaomi Mobile Data Keeps Disconnecting? UK Fix

If your Xiaomi mobile data keeps disconnecting randomly, internet keeps dropping, or data stops working until you toggle Airplane mode, this guide will help you fix it.

Quick Answer:
If your Xiaomi mobile data randomly disconnects throughout the day, first check your Network type – set it to 4G/3G/2G auto instead of "5G only" to improve stability. Then turn off Battery Saver and Data Saver, as both can restrict background data. If disconnections persist, reset APN settings and reset network settings. In many cases, the issue is caused by 5G switching or power-saving features.

Applies to Redmi, POCO and Xiaomi Phones

This guide applies to Xiaomi, Redmi and POCO devices running MIUI or HyperOS on all UK carriers – EE, O2, Vodafone, Three, and their MVNOs.

Users in London, Manchester, Birmingham, Glasgow and Leeds often report random data drops when phones repeatedly switch between 4G and 5G coverage areas.

🔍 Quick Start – Find Your Path

Symptom	Most Likely Cause	Go To
Data disconnects when screen is off	Battery Saver or Data Saver	Section 1
Data disconnects when switching between 4G/5G	Network switching issue	Section 2
Data disconnects after moving location	Mast handover failure	Section 3
Data disconnects at specific times of day	Network congestion or carrier issue	Section 4
Data disconnects randomly anywhere	APN or network settings issue	Section 5

Section 1 – Data Disconnects When Screen Is Off (Most Common)

If mobile data disconnects when your screen turns off, the issue is often Battery Saver or Data Saver restricting background data. In many cases, Battery Saver, Data Saver, or aggressive background restrictions can interrupt mobile data activity when the screen is off. However, other factors like Wi-Fi Assist, Smart Network Switching, carrier bugs, or aggressive app optimisation can also cause this behaviour.

Try these in order:

1. Turn off Battery Saver – Settings → Battery → Battery saver → OFF.
2. Turn off Data Saver – Settings → SIM cards & mobile networks → [Your carrier] SIM → Data saver → OFF.
3. Disable "Clear cache when device is locked" – Settings → Battery → Additional features → Clear cache when device is locked → OFF.
4. Remove battery restrictions for network services – Settings → Apps → Manage apps → search for "Phone" or "Network" → Battery saver → Set to "No restrictions".
5. Disable Smart Network Switching – Settings → Connection & sharing → Network settings → Turn OFF "Auto switch between WiFi and mobile data" (if available).

Section 2 – Data Disconnects When Switching Between 4G and 5G

If data disconnects when your phone switches between 4G and 5G, the issue is usually 5G instability or incorrect network settings. This is a common reason why Xiaomi internet keeps dropping or Redmi data connection is lost.

Try these in order:

1. Switch to 4G only – Settings → SIM cards & mobile networks → [Your carrier] SIM → Preferred network type → select 4G/3G/2G auto. 5G switching can cause brief disconnections.
2. Disable 5G SA mode if available – On some devices, Settings → Additional settings → Developer options → 5G network mode → Select "NSA only" (if available). This option may not be present on all devices.
3. Toggle Airplane mode – ON for 30 seconds, then OFF. This forces a fresh connection to the network.

Section 3 – Data Disconnects When Moving (Mast Handover)

If data disconnects when you move between locations (walking, driving, or travelling), the phone may be struggling to switch between masts.

Try these in order:

1. Switch to 4G – Set Preferred network type to 4G/3G/2G auto. 5G handover can be less stable.
2. Toggle Airplane mode – ON for 30 seconds, then OFF. This forces reconnection to the nearest mast.
3. Check whether the issue occurs on trains or motorways only – High-speed movement can cause frequent mast switching. If the issue only happens on trains, it's likely network-related.
4. Force 4G and test for several days – This helps determine if the issue is 5G-related or a broader network problem.
5. Remove and reinsert the SIM card – Power off → remove SIM → clean contacts → reinsert firmly.
6. Check for carrier updates – Some carriers send network updates via system updates. Check Settings → About phone → System update.
7. Request a replacement SIM from the carrier – If the SIM is several years old, it may lack modern network profiles.

Section 4 – Data Disconnects at Specific Times of Day

If data disconnects at the same times every day (e.g., 9am, lunchtime, 5pm), the issue is likely network congestion or carrier-side.

What to do:

• No phone setting will fix congestion – it's a network capacity issue.
• Try 4G instead of 5G – 4G may be less congested.
• Test at different times – If the problem only occurs during peak hours, congestion is confirmed.
• Contact your carrier – Ask if there are known issues in your area.

Section 5 – Data Disconnects Randomly Anywhere

If data disconnects randomly and none of the above sections match, the issue is likely APN, network settings, or SIM-related. This is often the case when Xiaomi data stops working until airplane mode is toggled.

Try these in order:

1. Reset APN to default – Settings → SIM cards & mobile networks → [Your carrier] SIM → Access Point Names → three dots → Reset to default → Restart.
2. Check preferred network type – Settings → SIM cards & mobile networks → [Your carrier] SIM → Preferred network type → Select 5G/4G/3G auto or 4G/3G/2G auto.
3. Disable and re-enable the SIM – Settings → SIM cards & mobile networks → Turn SIM OFF → wait 30 seconds → Turn SIM ON.
4. Check for a carrier settings update – Install any available HyperOS updates, as carrier profiles are sometimes updated through system updates.
5. Test your SIM in another phone – If the problem follows the SIM, contact your carrier for a replacement.
6. Reset network settings – Settings → Connection & sharing → Reset Wi-Fi, mobile networks, and Bluetooth (last resort – removes saved Wi-Fi passwords).

Why Does Mobile Data Randomly Disconnect?

• Battery Saver or Data Saver (most common) – Restricts background data and can cause disconnections when screen is off.
• 5G switching – Switching between 4G and 5G can cause brief disconnections.
• Mast handover – Moving between masts can cause temporary drops.
• Network congestion – Too many users on the same mast during peak hours.
• Carrier issue – Temporary network problems or maintenance.
• APN or network settings – Incorrect APN or corrupted network settings.

⚠️ What NOT to Do

• Don't factory reset your phone – Random disconnections are rarely solved by a factory reset.
• Don't assume your phone is faulty – Test your SIM in another phone first.
• Don't ignore carrier-side issues – If the problem is the network, no phone setting will fix it.

Quick Questions

Why does my Xiaomi mobile data keep disconnecting when screen is off?
This is often Battery Saver or Data Saver. Turn them both off to prevent background data restrictions.

Does 5G cause random disconnections?
5G switching can be unstable in some areas. Switching to 4G often resolves the issue.

How do I fix mobile data dropping when I move?
Switch to 4G and toggle Airplane mode when you change location.

Will resetting network settings fix random disconnections?
It can help if APN or network settings are corrupted. Try other fixes first.

Why does my data disconnect at the same time every day?
This is usually network congestion during peak hours. Try 4G or contact your carrier.

Why does mobile data start working again after Airplane mode?
Airplane mode forces your phone to disconnect and reconnect to the mobile network. This can temporarily resolve network registration issues.

Why do I need to restart my Xiaomi to get mobile data back?
This usually indicates a network registration, APN, or carrier-related issue rather than a hardware fault.

Why does my Xiaomi show 4G or 5G but mobile data doesn't work?
A phone can remain connected to the network while mobile data services fail. Airplane mode temporarily reconnects the device and may restore data access.