How to Fix Mobile Data That Is Not Working on Your Phone

Published 2026-10-16 · Marion Phone Repair

Your phone connects to Wi-Fi fine but mobile data does not work. You leave the house or the Wi-Fi range and suddenly have no internet. Web pages do not load, apps say no connection, and streaming stops. The signal bars show a connection to the cell tower but there is no data. Or you see the LTE or 5G icon but nothing actually loads. Mobile data problems are caused by incorrect settings, account issues, network congestion, SIM card problems, or software glitches.

Check the obvious settings first

Make sure mobile data is turned on

Android: Pull down the notification shade and look for the Mobile Data tile. Make sure it is toggled on (highlighted). Or go to Settings, Network and Internet (or Connections), Mobile Network — make sure Mobile Data is toggled On
iPhone: Settings, Cellular — make sure Cellular Data is toggled On at the top. Also check the list of apps below — each app has its own toggle for cellular data access. If a specific app does not work on data, its toggle may be Off

Check Airplane Mode

Make sure Airplane Mode is Off. When Airplane Mode is on, all wireless radios including cellular data are disabled. Toggle it off in the quick settings panel or Settings
A useful trick: turn Airplane Mode ON, wait 10 seconds, then turn it OFF. This forces the phone to reconnect to the cell tower from scratch and often fixes temporary connection issues

Check for a data limit

Android: Settings, Network and Internet, Mobile Network, Data Usage (or Data Warning and Limit). Android can automatically disable mobile data when you reach a self-set data limit. If the limit is set too low, data stops working mid-month. Increase the limit or disable it
iPhone: iOS does not have a built-in data limit that shuts off data, but some carrier apps or parental control apps do. Check for any data management apps that may be blocking data

Restart the phone

A restart fixes a surprising number of mobile data issues because it clears stuck network processes, releases stale connections, and forces the phone to re-register with the cell tower:

Power off the phone completely (not just restart — actually power off), wait 30 seconds, then power it back on
After the restart, wait 1 to 2 minutes for the phone to fully register with the network before testing data

Check your account and plan

Mobile data problems are sometimes not a phone issue at all — they are an account issue:

Unpaid bill: If your bill is overdue, the carrier may suspend data service while keeping calls and texts active. Check your carrier app or account online
Data cap reached: Many plans throttle data speeds to near-unusable levels (128 kbps or slower) after reaching a monthly data cap. The phone shows a data connection but nothing loads because the speed is too slow. Check your data usage in the carrier app
Plan does not include data: Some very basic plans (especially prepaid) may not include mobile data or may require a separate data add-on. Verify your plan includes data
Account suspended: Carriers can suspend accounts for various reasons including fraud alerts, payment failures, or SIM swap attempts. Call your carrier's customer service number or visit a store

SIM card troubleshooting

The SIM card authenticates your phone with the carrier network. A loose, dirty, or damaged SIM can cause data failures:

Power off the phone
Remove the SIM card tray using the SIM eject tool or a paperclip
Take the SIM card out and inspect it for visible damage — scratches on the gold contacts, chips, or bending
Clean the gold contacts gently with a soft dry cloth
Reinsert the SIM card, making sure it sits properly in the tray (flat, correct orientation, not tilted)
Power on and test data

eSIM users

If you use an eSIM (no physical SIM card), you cannot remove and reseat it. Instead, check Settings, Cellular (iPhone) or Settings, Network, SIM (Android) to make sure the eSIM is active and selected as the data line
For dual SIM phones (physical + eSIM or two eSIMs), make sure the correct line is set as the cellular data line. Settings, Cellular, Cellular Data — select the line with your data plan

Reset network settings

This resets all network configurations back to factory defaults, fixing corrupted APN settings, broken VPN configurations, and stuck network preferences:

Android

Settings, System (or General Management), Reset, Reset Network Settings
This erases saved Wi-Fi passwords, Bluetooth pairings, VPN configurations, and cellular settings. You will need to reconnect to Wi-Fi networks afterward
After the reset, restart the phone and test mobile data

iPhone

Settings, General, Transfer or Reset iPhone, Reset, Reset Network Settings
Same as Android — Wi-Fi passwords and VPN settings are erased. The phone restarts automatically
After restart, test mobile data before reconnecting to Wi-Fi

Check and reset APN settings

The APN (Access Point Name) tells the phone how to connect to the carrier's data network. Incorrect APN settings mean the phone can connect to the cell tower for calls but cannot route data:

Android

Settings, Network and Internet (or Connections), Mobile Network, Access Point Names
You should see one or more APNs listed for your carrier. If the list is empty, the APN was deleted or never configured
Tap the three-dot menu and select Reset to Default. This restores your carrier's default APN settings
If Reset to Default is not available, you can manually add the APN. Search your carrier's website for APN settings (each carrier publishes their correct APN values) and enter them manually

iPhone

iPhones typically manage APN settings automatically through the carrier settings update. Settings, General, About — if a carrier settings update is available, a prompt appears. Install it
To reset cellular settings on iPhone: Settings, Cellular, Cellular Data Network — you can see and edit APN fields. If they are blank or incorrect, contact your carrier for the correct values

Check for carrier outages

If mobile data stopped working suddenly for no apparent reason, the carrier may be experiencing a network outage in your area
Check the carrier's website or social media accounts for outage reports. Sites like DownDetector show real-time outage maps for all major carriers
Ask someone else on the same carrier in your area if their data is working. If nobody on that carrier has data, it is an outage

Software troubleshooting

Update the phone

Install any pending software updates. Carrier connectivity fixes are sometimes included in system updates. Check Settings, System, Software Update (Android) or Settings, General, Software Update (iPhone)

Check for VPN interference

VPN apps can interfere with mobile data routing. If you have a VPN app installed (NordVPN, ExpressVPN, Surfshark, or a corporate VPN), disable it and test data. Some VPN apps remain active even when you think they are off

Safe Mode test (Android)

Boot into Safe Mode: hold the power button, long-press Power Off, select Safe Mode (or OK)
In Safe Mode, only system apps run. Test mobile data — if it works in Safe Mode, a third-party app is interfering with the data connection
Common culprits: VPN apps, firewall apps, data saver apps, ad blockers that route traffic through a local VPN, and battery optimization apps that aggressively restrict background data

Hardware issues

Damaged antenna: If the phone was dropped or exposed to water, the cellular antenna may be damaged. Symptoms include weak signal, frequent signal drops, and data that works intermittently
SIM card slot damage: A bent pin in the SIM card slot can prevent proper contact with the SIM, causing intermittent data failures. This sometimes happens when inserting the SIM tray at an angle
Baseband chip failure: The baseband processor handles all cellular communication. If it fails, the phone may show No Service or have permanent data issues. This is a motherboard-level hardware failure

Mobile data repair in Marion

If your phone mobile data is not working and the troubleshooting above did not fix it, Marion Phone Repair can diagnose whether the issue is a SIM card problem, a software or APN configuration issue, an antenna or hardware failure, and restore your mobile data connection.