Can’t Make or Receive Calls but Mobile Data Works?

Your phone says 4G or 5G.

Websites load.

You can stream music.

WhatsApp messages arrive.

But normal phone calls?

Nothing.

This usually means your phone has successfully connected to the network for mobile data, while the part of the service handling voice calling has failed to register or operate correctly.

In the UK in 2026, one of the most important things to check is VoLTE.

All major UK 3G networks have now been switched off, so phones can no longer rely on 3G as the old fallback for ordinary calls.

If 4G/5G data works but normal calls do not, check VoLTE, handset compatibility, network mode, SIM provisioning, account status and your provider’s voice service.

Why Can Mobile Data Work When Calls Don’t?

Because “mobile service” is not one single pipe.

Your SIM and phone interact with different network systems for:

• data
• voice
• SMS
• authentication
• emergency services
• roaming

A phone can therefore register successfully for one service while another is unavailable.

Think about home broadband.

Your internet connection can work even when a separate landline telephone service has a fault.

Mobile networks are more integrated than that example, but the principle is similar.

A good data session does not prove the voice layer is healthy.

The 2026 Difference: 3G Is Gone in the UK

Older troubleshooting advice often says:

“Switch to 3G and test the call.”

That is now outdated in the UK.

Ofcom confirms that Vodafone, EE, Three and O2 have all completed their 3G network switch-offs.

The remaining older technology is 2G on networks that still operate it, but 2G is also being gradually phased out over the coming years.

That means modern voice calling increasingly relies on VoLTE.

What Is VoLTE?

VoLTE stands for:

Voice over LTE

LTE is the technology commonly associated with 4G.

VoLTE allows ordinary mobile phone calls to run over the 4G network instead of requiring the phone to fall back to older 2G or 3G technology.

Talk Home Mobile describes VoLTE as enabling compatible phones to remain on 4G LTE during calls.

Without working VoLTE, an older device might attempt to fall back to 2G.

And as legacy networks shrink, relying on fallback becomes increasingly fragile.

How to Tell Whether VoLTE Is Working

Try making a phone call.

Watch the network indicator.

If it remains on 4G/LTE

VoLTE is probably working.

If it drops from 4G to 2G

The phone is likely using legacy voice fallback.

If the call fails completely

VoLTE may not be registering and usable fallback may be unavailable.

Talk Home Mobile uses essentially this test in its own VoLTE guidance: a supported call should stay on 4G/LTE rather than dropping to an older network.

Why Would VoLTE Stop Working?

Several possibilities.

The phone does not support VoLTE

Very old 4G phones sometimes support LTE data without properly supporting modern carrier VoLTE profiles.

VoLTE is switched off

Some phones expose a:

• VoLTE
• 4G Calling
• Voice over LTE

setting.

The software is outdated

Carrier profiles and operating-system updates can affect network compatibility.

The SIM is old or incorrectly provisioned

Your account may need the correct voice service enabled.

The handset firmware isn’t compatible with the provider

A device can technically support VoLTE but still need correct carrier configuration.

This is why:

“My phone has 4G”

does not automatically mean:

“My phone can make calls over 4G.”

Check Your Network Mode

Phones often provide options such as:

• 5G/4G/2G automatic
• 4G/3G/2G
• LTE only
• 2G only

Names vary.

For most users, automatic network selection is safer than forcing an unusual mode.

A phone forced into an incompatible network configuration can end up with working data but failed calling.

If you previously changed network settings while travelling or troubleshooting something else, restore the recommended automatic mode.

Make Sure the SIM Line Is Enabled

Dual-SIM phones can create surprisingly confusing faults.

You might be using:

• SIM 1 for data
• SIM 2 for calls

If the voice line is disabled while the data SIM remains active, the phone can appear fully connected even though the number you expect to use for calling is unavailable.

Check:

• both SIMs enabled
• correct default voice SIM
• correct mobile-data SIM
• correct number displayed

This is particularly important after:

• adding an eSIM
• travelling
• swapping physical SIMs
• changing plans

Toggle Aeroplane Mode

Switch it on.

Wait around five seconds.

Switch it off.

This forces a new network registration.

Apple includes this simple step in current call troubleshooting guidance.

If the issue is a temporary registration problem, the voice service may return after reconnection.

Restart the Phone

Do a real restart.

Not:

screen off → screen on.

A restart reloads the phone’s modem and networking services.

If VoLTE or SIM registration became temporarily stuck, this can help.

Check Whether the Account Can Make Calls

Do not assume the handset is responsible.

Possible account-level causes include:

• suspended service
• expired plan
• insufficient credit
• call barring
• incomplete activation
• provisioning fault

Mobile data might still work in some account states while voice behaves differently.

Check the provider dashboard or account status.

New SIM? Activation and Plan Activation Are Different

This matters especially after changing SIMs.

For Talk Home Mobile, current guidance says a normal new SIM generally activates automatically when inserted, while *123*9# can be used if automatic activation does not complete.

Talk Home also explains separately that customers may need to activate or purchase the actual mobile plan.

Those are different things.

SIM activation

The network recognises the SIM.

Plan activation

Your minutes, texts and data allowance are attached and ready.

A person can easily confuse the two.

Test Wi-Fi Calling

If your mobile provider supports it, Wi-Fi Calling can tell you something useful.

Ofcom recommends Wi-Fi Calling as one solution where mobile reception is weak indoors.

Talk Home Mobile supports Wi-Fi Calling on compatible phones.

If:

normal mobile calls fail

but:

Wi-Fi Calling works

the underlying cellular voice connection may be the problem rather than your number itself.

Does Having 5G Automatically Fix Calling?

No.

5G data appearing in your status bar does not automatically prove that your voice configuration is correct.

Depending on the network and handset, voice calling can involve different network architecture from your active data session.

For everyday troubleshooting, the important point is simple:

Do not diagnose voice health using the data icon alone.

Your phone can show 5G and still have a voice-registration issue.

Can APN Settings Cause Call Problems?

APN settings mainly relate to mobile data connectivity.

So if your internet already works, changing APNs randomly is usually not the first thing to do for a voice-only failure.

This is where generic internet troubleshooting can make things worse.

Do not start editing obscure fields because someone on a forum posted a screenshot from a different provider in 2021.

Voice failures require voice-focused diagnostics.

What About Call Barring?

Call barring can prevent:

• outgoing calls
• incoming calls
• international calls
• certain categories of calls

If both incoming and outgoing calls fail while everything else works, account-level call restrictions are worth checking.

The exact controls depend on the provider.

If you never intentionally enabled barring, ask support to confirm whether any voice restriction exists on the account.

Try Another Location

Ofcom recommends checking whether a mobile fault happens everywhere or only in one place.

Go outside or travel a short distance.

Test again.

Calls work elsewhere

Local coverage/network conditions become more likely.

Calls fail everywhere

Handset, SIM or account issues move higher up the list.

Test the SIM in Another Compatible Phone

Again, one of the best tests.

Put the SIM into another unlocked device that supports modern UK voice services.

Calls work

Original handset/settings problem.

Calls fail

SIM/account/network problem becomes more likely.

Be careful when using a very old spare handset.

If it does not support modern VoLTE, it may not be a valid comparison.

Why Older Phones Are Becoming More Problematic

A phone can look perfectly usable.

Screen fine.

Battery fine.

4G data fine.

But if it relies on legacy network technology for voice, UK network modernisation can expose that limitation.

Ofcom advises customers with older devices to check compatibility as 2G and 3G services are retired.

This is especially important for:

• older smartphones
• imported models
• niche devices
• feature phones
• devices with outdated firmware

The phone doesn’t need to be physically broken.

It may simply be increasingly mismatched with the modern network.

A Real-Life Example

James has an older 4G phone.

He notices YouTube works perfectly.

Emails arrive.

Google Maps loads.

But every normal phone call immediately fails.

His first thought:

The network can’t be down because data works.

Correct.

But that doesn’t prove voice works.

During a call attempt, the device drops from 4G to an older network indicator.

That points towards a voice fallback problem.

After checking, he discovers the handset isn’t properly using VoLTE with the current provider.

The issue was not:

signal vs no signal.

It was:

data-capable vs voice-capable on the current network setup.

Talk Home Mobile Customers: What to Check

Talk Home Mobile supports VoLTE and Wi-Fi Calling on compatible smartphones.

If Talk Home data works but normal calls do not:

1. update your handset software
2. check VoLTE/4G Calling
3. restart the phone
4. verify your plan/account
5. test Wi-Fi Calling
6. try the SIM in another compatible handset
7. contact support if voice still fails

Do not immediately assume strong data means the SIM is fully provisioned for every service.

Don’t Confuse App Calls With Mobile Calls

WhatsApp, FaceTime and similar services use your internet connection.

So this can happen:

WhatsApp call works.

Normal phone call fails.

That does not mean the phone’s “calling” is fine.

It means the internet works.

Those are different services.

This distinction is extremely useful when describing the problem to support.

Say:

“Mobile data and WhatsApp calls work, but normal cellular voice calls fail.”

That is specific.

A Quick Diagnostic Table

What Works?	Likely Area to Check
Data only	VoLTE / voice registration
Data + SMS	Voice provisioning / VoLTE
Wi-Fi Calling only	Cellular voice coverage
Calls on another phone	Original handset
SIM fails in multiple phones	Account/SIM/network
Calls drop to 2G	VoLTE not being used
Everything works except one destination	Call restriction/routing

When Should You Contact Your Provider?

Do so when:

• the problem happens everywhere
• another compatible phone behaves the same way
• VoLTE cannot register
• calls suddenly stopped after a SIM change
• account status looks normal
• mobile data and SMS continue to work

Tell them exactly what you tested.

That avoids going through twenty generic scripts before reaching the real issue.

Mobile Data Working Is Good News

It means your phone is at least connecting to the network.

But it does not prove that voice calling is configured correctly.

In the modern UK mobile environment, VoLTE is no longer a nice technical extra hidden in the settings.

It is increasingly central to normal calling.

With 3G gone and 2G on the way out, phones need to be ready to handle voice on newer network technology.

So if your data flies while ordinary calls refuse to cooperate, don’t stare at the signal bars.

Check the voice layer.