eSIM not working? Fix no service and activation errors

Key takeaways

  • An eSIM that isn't working usually needs one of a few quick fixes: restart the phone, switch Airplane mode on and off, check that the eSIM line is turned on, and install over a strong Wi-Fi connection.
  • A SMARTY eSIM usually activates straight away, but it can take up to two hours. A short wait is normal and doesn't mean anything's wrong.
  • If the basics don't work, ask your network for a new eSIM rather than deleting the one you have, because many QR codes only work once.

 

No signal on a phone you've only just set up is stressful, and it's even worse when you can't call anyone to ask why.

Most eSIM problems are minor and can be fixed in a few minutes. Use the table below to work out what's going on, then try the fixes in order. New to eSIMs? Our guide to what an eSIM is covers the basics.

What's wrong with your eSIM? A quick diagnosis

Find what you're seeing in the left-hand column, then jump to the fix.

What you see What to try first
No service or no signal bars Check the eSIM line is on, then restart the phone and switch Airplane mode on and off.
eSIM stuck on activating Wait up to two hours, then restart and make sure the phone is on strong Wi-Fi.
Unable to activate eSIM, or the QR code won't scan Use the latest QR code, enter the confirmation code carefully, or ask for a new eSIM.
Mobile data not working Pick the eSIM for mobile data and switch Wi-Fi off to test.
iMessage or texts not working Switch iMessage off and on again, then restart the phone.
Old physical SIM stopped working Nothing is broken. Keep using the eSIM, or ask your network for a new physical SIM.
Transfer to a new phone failed Ask your network for a new QR code and scan it on the new phone.

Why is my eSIM not working? Eight fixes to try in order

If your eSIM isn't working, work through these in order and check for signal after each one.

  1. Give it a little time. A SMARTY eSIM usually activates straight away, but it can take up to two hours.
  2. Restart your phone. Switch it off completely, wait about 30 seconds, then switch it back on.
  3. Switch Airplane mode on and off. Leave it on for a few seconds, then turn it off so the phone searches for the network again.
  4. Check that the eSIM line is turned on. On an iPhone, go to Settings, then Mobile Service (shown as Cellular on some phones), tap your eSIM, and make sure the line is on. On a Pixel, go to Settings, Network & internet, then SIMs, and turn on Use SIM. On a Samsung, go to Settings, Connections, then SIM Card Manager.
  5. Choose the eSIM for calls, texts and mobile data. Set the eSIM as your mobile data line, then switch Wi-Fi off to test it. Wi-Fi can make everything look fine when it isn't.
  6. Update your phone. Install the latest software update, then restart.
  7. Check that your phone supports eSIM and is unlocked. Dial *#06# and look for an EID number. If one appears, the phone supports eSIM. Our list of eSIM-compatible phones has the details.
  8. Check your plan and the network. If a renewal payment fails, a SMARTY plan pauses. Incoming calls and texts still work, but outgoing calls, texts and data don't. SMARTY's Network Status Checker also shows any faults or maintenance in your area.

Resist the urge to delete the eSIM and start again. Many QR codes work only once, so deleting it can leave you waiting for a new one. A SMARTY QR code can be used once and expires after 60 days.

How long does an eSIM take to activate?

With SMARTY, an eSIM usually activates immediately after you scan the QR code and enter your confirmation code. Occasionally, it can take up to two hours.

Two other waits are worth knowing about:

  • The QR code email can take up to two hours to arrive. Check your junk and spam folders first. If it hasn't arrived after two hours, contact SMARTY Customer Care.
  • The confirmation code is separate. New customers receive the 4-digit code in a second email. Customers replacing a SIM can find it in their SMARTY dashboard.

How to activate an eSIM and check it worked

  1. Connect to strong, stable Wi-Fi.
  2. Open the email with your QR code and activation details.
  3. On an iPhone, go to Settings, then Mobile Service, then Add eSIM. On a Samsung, go to Settings, Connections, then SIM Card Manager. On a Pixel, go to Settings, Network & internet, then SIMs.
  4. Scan the QR code. If you can't scan it, enter the activation code by hand.
  5. Enter the 4-digit confirmation code when your phone asks. It may call it a PIN, or a Three confirmation code, because SMARTY runs on the Three network.
  6. Switch Wi-Fi off, then make a call or send a text to check you're connected.

eSIM not working on iPhone or Android

The basic fixes are the same on every phone. These extra steps are specific to each type.

eSIM not working on iPhone

Apple's eSIM help suggests this order:

  1. Switch Airplane mode on and off.
  2. Go to Settings, then Mobile Service (shown as Cellular on some phones), tap your eSIM, and switch that line off and back on.
  3. Restart the iPhone.
  4. Go to Settings, General, then About. If a carrier settings update is available, your iPhone will offer it.
  5. Check you're running the latest iOS.

eSIM not working on Android

Menus vary by brand, so the names may differ slightly. On a Pixel, Google's connectivity help is a good guide:

  1. Go to Settings, Network & internet, then SIMs. Make sure Use SIM and Mobile data are both on for your eSIM.
  2. Switch Wi-Fi off, then check the signal indicator in the status bar.
  3. Turn off Battery Saver, which can switch 5G off.
  4. Power the phone off, wait 30 seconds, then switch it back on.
  5. As a last resort, reset your mobile network settings. On a Pixel, that's under Settings, System, then Reset options.

Unable to activate eSIM

These messages usually mean the phone couldn't complete eSIM setup with the network. With SMARTY, the most common causes are weak Wi-Fi or a mistyped code, so try this:

  • Connect to a strong, stable Wi-Fi network.
  • Re-enter the 4-digit confirmation code carefully. You only have a limited number of attempts.
  • Use the manual activation code if scanning fails. On an iPhone, you'll also need the SM-DP+ address from your eSIM email.
  • Ask for a new eSIM if you've already seen an error. Do it from your dashboard or by contacting Customer Care.

eSIM data, calls, texts or iMessage not working

Sometimes the eSIM is active, but one thing won't work. Here's where to look.

eSIM mobile data or hotspot not working

  • Set the eSIM as your mobile data line. Check the setting, then switch Wi-Fi off and test again. Apps such as WhatsApp rely on mobile data, so sort this first.
  • Restart the phone. A hotspot shares your phone's mobile data connection, so fix the data first, then try the hotspot again.
  • Check your APN only if data still won't connect. Most phones set this up automatically. For SMARTY, the mobile data APN is mob.asm.net, with the username left blank.

eSIM calls or texts not working

  • Check the right line is chosen. If your phone has two lines, make sure the eSIM is set as the default for calls and texts.
  • Check your plan is active. A SMARTY plan pauses if a renewal payment fails. Incoming calls and texts still work, but outgoing calls, texts and data don't.

iMessage not working after switching to an eSIM

Your number has moved to a new SIM, so your iPhone may need to confirm it with Apple again. Apple's iMessage and FaceTime help suggests this order:

  1. Go to Settings, Apps, then Messages, and turn iMessage off.
  2. Do the same for FaceTime.
  3. Restart the iPhone.
  4. Turn iMessage and FaceTime back on.

If a spinning gear appears next to your number, the iPhone is still checking it, so wait rather than switching iMessage on and off again. Activation can take up to 24 hours.

eSIM transfer to a new phone not working

An eSIM is built into the phone, so it can't be moved like a card. It has to be set up again on the new phone, either with a phone-to-phone transfer or with a new QR code from your network. Check our full guide on how to transfer an eSIM to a new phone, which covers each step.

If you're on SMARTY

If your SMARTY eSIM still isn't working, here's the quickest way to get moving again:

  • Get a fresh eSIM. In your dashboard, go to Account settings, then Manage plan, then Replace SIM. Choose Activate now only when you're ready to set up, because it disconnects your current SIM straight away.
  • Chat to Customer Care. Webchat is open from 8am to 8pm, seven days a week.
  • Check the help centre. It has step-by-step guides on eSIM activation errors and where to find your eSIM confirmation code.

Not with SMARTY yet? Choose eSIM at checkout and you can be up and running in a few minutes. Have a look at all SMARTY plans.

FAQs

Why is my eSIM not working?

An eSIM usually isn't working because its line is switched off, activation hasn't finished, the phone needs a restart, or a QR code or confirmation code was entered incorrectly. Restarting the phone, switching Airplane mode on and off, and checking that the eSIM line is turned on fix most cases.

How long does an eSIM take to activate?

A SMARTY eSIM usually activates immediately after you scan the QR code and enter the 4-digit confirmation code. Occasionally, it can take up to two hours.

Can I use an eSIM QR code twice?

A SMARTY eSIM QR code can be used only once and expires after 60 days or as soon as you enter the confirmation code, whichever comes first. If a QR code has been used or has expired, get a replacement eSIM from your SMARTY dashboard.

SMARTY Team
  • SMARTY Team
  • SMARTY
  • October 21st, 2026