Before you start
- Your SIM PIN, if your SIM has one
- A Wi-Fi connection helps for updates
Method 1 Quick fixes
-
Step 1: Check coverage and outages
Move near a window or outdoors and see if other people on your network have signal. Check your network’s website or social media for outages.
-
Step 2: Toggle airplane mode
Turn on Airplane Mode, wait 10 seconds, then turn it off. This forces the phone to search for the network again.
-
Step 3: Restart the phone
Turn the phone fully off and on again.
Method 2 Check the SIM or eSIM
-
Step 1: Make sure the line is on
iPhone: Settings > Cellular, tap the line and check Turn On This Line. Android: Settings > Network & internet > SIMs (Samsung: Connections > SIM manager) and check the SIM is on.
-
Step 2: Reinsert a physical SIM
Turn the phone off, eject the SIM tray, check the SIM for damage, wipe it gently and put it back.
-
Step 3: Test in another phone
If the SIM doesn’t work in another phone either, the SIM is faulty or blocked. Your network can replace it, usually keeping your number.
Method 3 Update and choose the network
-
Step 1: Update the phone
Install software updates. On iPhone, also check for a carrier settings update in Settings > General > About.
-
Step 2: Select the network manually
iPhone: Settings > Cellular > Network Selection, turn off Automatic and pick your network. Android: Settings > Network & internet > SIMs and turn off Automatically select network (Samsung: Connections > Mobile networks > Network operators).
-
Step 3: Check the network mode
On Android, set Preferred network type or Network mode to the automatic option that includes 5G or 4G. Many networks have switched off 3G and 2G, so phones stuck on those modes lose service.
Method 4 Reset network settings
This removes saved Wi-Fi passwords, Bluetooth pairings and VPN settings, but not your photos or apps.
-
Step 1: iPhone
Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings.
-
Step 2: Google Pixel and most Android phones
Go to Settings > System > Reset options and choose Reset mobile network settings (or Reset Wi-Fi, mobile & Bluetooth).
-
Step 3: Samsung Galaxy
Go to Settings > General management > Reset > Reset network settings.
Method 5 Contact your network
-
Step 1: Check your account and SIM registration
Unpaid bills, an unregistered SIM or a SIM not linked to your ID (required in many countries) can cut service.
-
Step 2: Check the phone isn’t blocked
Dial *#06# to see your IMEI and ask the network to confirm it isn’t blacklisted or locked to another carrier.
-
Step 3: Ask about phone compatibility
Older phones without 4G calling (VoLTE) can stop working when networks retire 3G.
Troubleshooting
No service only after a drop or water damage
The antenna or SIM reader may be damaged. Back up your phone and have it checked by an authorised repair centre.
No service only at home
Thick walls and basements block signal. Turn on Wi-Fi Calling so calls and texts work over your home Wi-Fi.
Frequently asked questions
Will a factory reset fix No Service?
Rarely. Try a network settings reset first; a full reset deletes your data and usually isn’t needed.
Why does my phone say SIM not supported?
The phone is probably locked to another network. Ask the original carrier to unlock it.
Summary
Toggle airplane mode, restart, check the SIM or eSIM line is on, then update the phone, pick your network manually and reset network settings. If there’s still no service, your network can check outages, your account, SIM registration and whether the phone is blocked.
