Mobile Phone Problems: Quick Fixes
Step-by-step solutions for common mobile phone problems. Fix signal issues, data problems, call failures, and more.
No Signal / No Service
Based on reader feedback and our own testing, here are the most effective solutions for common mobile problems.
Quick Fixes
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Toggle Airplane Mode
Turn Airplane mode on, wait 30 seconds, then turn it off. This forces your phone to reconnect to the network.
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Restart your phone
A simple restart can fix many network connection issues.
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Check for network outages
Visit your network's status page or use DownDetector to check for outages in your area.
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Remove and reinsert SIM
Power off, remove the SIM, wait a moment, reinsert and power on.
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Reset network settings
As a last resort, reset network settings (you'll need to re-enter Wi-Fi passwords).
If Problems Persist
- Test your SIM in another phone to rule out SIM issues
- Test another SIM in your phone to rule out phone issues
- Check if your account is active and bills are paid
- Contact your network for a replacement SIM if needed
Mobile Data Not Working
Step-by-Step Fix
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Check mobile data is enabled
Go to Settings > Mobile Data and ensure it's switched on.
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Check data allowance
You may have used all your data. Check in your network's app.
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Disable Low Data Mode / Data Saver
These modes can restrict data for some apps.
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Check APN settings
Incorrect APN settings prevent data connections. Contact your network for correct settings.
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Toggle 4G/5G off and on
Try switching to 3G temporarily, then back to 4G/5G.
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Reset network settings
Go to Settings > General > Reset > Reset Network Settings.
Call Problems
Can't Make Calls
- Check you have signal bars
- Disable Airplane mode
- Try dialling with country code
- Check if number is blocked
- Restart your phone
Can't Receive Calls
- Check Do Not Disturb is off
- Check call forwarding settings
- Verify phone isn't on silent
- Check caller isn't blocked
- Toggle Airplane mode
Calls Dropping
- Move to area with better signal
- Enable Wi-Fi Calling
- Check for network congestion
- Update phone software
- Report persistent issues to network
Poor Call Quality
- Move to stronger signal area
- Enable VoLTE if available
- Try Wi-Fi Calling instead
- Clean microphone/speaker
- Test with another phone
Other Common Issues
Texts not sending
Voicemail not working
Slow internet speeds
Phone overheating
Battery draining quickly
When to Contact Your Network
Contact your network if:
- Problems persist after trying all troubleshooting steps
- You suspect a SIM card fault
- Your account may be suspended or restricted
- There's a confirmed network outage affecting your area
- You need APN settings sent to your phone
- You're experiencing widespread issues affecting multiple services
Network Connection Problems
Network connection issues are among the most frustrating mobile problems because they can prevent you from making calls, sending messages, and using the internet entirely. Understanding what causes these problems helps you fix them faster and know when it is a problem on your end versus a wider network outage.
No Signal Fixes
If your phone displays "No Service" or "Emergency Calls Only", the first step is to determine whether the problem is localised to your device or affecting others in your area. Ask someone nearby on the same network if they have signal. If they do, the issue is likely with your phone or SIM card. Try removing your SIM, cleaning the gold contacts gently with a dry cloth, and reinserting it. On iPhone, go to Settings, then General, then About, and if a carrier settings update is available, you will be prompted to install it. On Android, check for system updates under Settings, then Software Update.
If you are in a building with thick walls or a basement, poor signal indoors is common across all UK networks. Enabling Wi-Fi Calling is the single most effective solution for indoor coverage problems. All major UK networks support Wi-Fi Calling on compatible handsets, and it routes your calls and texts over your broadband connection instead of the mobile network. To enable it, go to Settings, then Phone (or Connections on Samsung), then Wi-Fi Calling, and toggle it on.
4G/5G Switching Issues
Some users experience connection drops when their phone constantly switches between 4G and 5G, particularly in areas where 5G coverage is patchy. This happens because the phone locks onto a 5G signal that is too weak to maintain a stable connection, then drops back to 4G, creating a cycle of disconnections. The fix is straightforward. Go to Settings, then Mobile Data, then Network Mode, and temporarily set it to 4G/LTE Only. This forces a stable 4G connection. Once you move to an area with strong 5G coverage, you can switch back to automatic mode.
APN Settings
Access Point Name settings tell your phone how to connect to your network's data service. Incorrect APN settings are a common cause of mobile data not working, especially after switching networks or performing a factory reset. Most networks send APN settings automatically when you insert a new SIM, but if data still does not work, you may need to enter them manually. Contact your network or visit their support page to find the correct APN, username, and authentication settings for your plan. On iPhone, go to Settings, then Mobile Data, then Mobile Data Network. On Android, go to Settings, then Connections, then Mobile Networks, then Access Point Names.
Network Settings Reset
If none of the above steps resolve your issue, performing a network settings reset clears all saved Wi-Fi passwords, Bluetooth pairings, VPN configurations, and cellular settings, returning them to factory defaults. This often resolves stubborn connection problems caused by corrupted network configuration data. On iPhone, go to Settings, then General, then Transfer or Reset iPhone, then Reset, then Reset Network Settings. On Android, go to Settings, then General Management, then Reset, then Reset Network Settings. Remember to reconnect to your Wi-Fi network afterwards, as saved passwords will be erased.
Phone Performance Issues
A slow or unresponsive phone is not always a sign that you need an upgrade. Many performance problems can be resolved with simple maintenance steps that restore your device to smooth operation.
Slow Phone Performance
If your phone feels sluggish, start by closing apps you are not using. On iPhones, swipe up from the bottom and swipe away app cards. On Android, tap the recent apps button and close unused apps. Next, restart your phone, as this clears temporary files and refreshes system processes. If the problem persists, check how much storage space is available. Phones with less than ten percent free storage often slow down significantly because the operating system needs free space for caching and swap operations. Delete unused apps, clear app caches, and move photos and videos to cloud storage or a computer.
Storage Full
When your phone warns that storage is almost full, the biggest culprits are usually photos, videos, and messaging app data. On iPhone, go to Settings, then General, then iPhone Storage to see a breakdown of what is using space. The same information is available on Android under Settings, then Storage. WhatsApp and Telegram can accumulate gigabytes of media over time. Open these apps and delete old conversations with large media attachments. You can also enable the "Offload Unused Apps" feature on iPhone, which removes app code but keeps data, freeing space without losing information.
Battery Drain
Rapid battery drain is often caused by a rogue app running in the background, poor signal forcing the phone to search constantly for a connection, or an ageing battery. Check your battery usage stats in Settings to identify which apps are consuming the most power. If a particular app is using a disproportionate amount of battery, try updating it or reinstalling it. On iPhones running iOS 16 or later, go to Settings, then Battery, then Battery Health to check your battery's maximum capacity. If it is below eighty percent, battery replacement may be worthwhile.
Overheating
Phones can overheat during intensive tasks like gaming, video recording, or when charging in direct sunlight. If your phone feels unusually hot, stop charging immediately, close all apps, and remove any case to allow heat dissipation. Avoid using the phone until it cools down naturally. Do not place it in a fridge or freezer, as rapid temperature changes can cause condensation inside the device, potentially damaging internal components. Persistent overheating outside of intensive use may indicate a hardware fault such as a failing battery, which should be examined by a professional repair service.
App and Software Problems
Apps crashing, freezing, or failing to update are common issues that usually have simple solutions. Before assuming the worst, work through these steps methodically.
Apps Crashing or Freezing
If a specific app keeps crashing, first check the App Store or Google Play Store for an update. Developers frequently release patches to fix bugs and compatibility issues. If the app is already up to date, try force-closing it and reopening. If crashes continue, delete the app and reinstall it from scratch. This clears any corrupted local data that might be causing the problem. Before deleting, check whether the app stores data in the cloud so you do not lose important information.
Software Update Issues
Failed software updates are often caused by insufficient storage space or an unstable internet connection. Before attempting a major operating system update, ensure you have at least five gigabytes of free storage and connect to a reliable Wi-Fi network. Charge your phone to at least fifty percent battery or keep it plugged in during the update. If an update repeatedly fails, try restarting your phone and attempting the update again. On iPhone, you can also try updating through a computer using Finder on Mac or iTunes on Windows, which sometimes succeeds when over-the-air updates fail.
Factory Reset as a Last Resort
If your phone has persistent software problems that none of the above steps resolve, a factory reset returns the device to its original state. This erases all data, apps, and settings, so it should only be used when all other troubleshooting has failed. Before performing a factory reset, back up your data using iCloud, Google Backup, or Samsung Cloud. On iPhone, go to Settings, then General, then Transfer or Reset iPhone, then Erase All Content and Settings. On Android, go to Settings, then General Management, then Reset, then Factory Data Reset. After the reset, set up your phone as new and reinstall apps individually to identify if a specific app was causing the problem.
Troubleshooting FAQ
Why does my phone say "Emergency Calls Only"?
How do I check if there is a network outage in my area?
Will a factory reset fix all phone problems?
My phone is stuck on the loading screen. What should I do?
Need Network-Specific Help?
Check our dedicated troubleshooting guides for O2 and Virgin Media customers.
Written by the AtlasMobile Team
Independent UK Mobile & Broadband Experts
Our editorial team combines over 25 years of experience in UK telecommunications. We research, test, and verify all information to provide accurate, unbiased guidance for consumers.
Last reviewed: January 2026