My eSIM Isn’t Working… What Should I Do?
Last Updated: July 10, 2026
4.5
You land in a new country, open your phone, and get hit with "No Service." Your eSIM isn't working, and you have no idea why. If this sounds familiar, you're not alone. eSIM not working issues are one of the most common support questions travelers face, and in most cases, the fix takes less than five minutes.
This guide walks you through exactly why your eSIM may not be working and gives you step-by-step fixes for both iPhone and Android.
Why Is My eSIM Not Working?
An eSIM stops working for a handful of predictable reasons: data roaming is off, the eSIM profile wasn't installed correctly, APN settings are wrong, your device is carrier-locked, or the eSIM hasn't been set as the active data line. In most cases, one of the 10 fixes below will solve the problem within minutes.
Common Reasons Your eSIM Is Not Working
Before diving into fixes, it helps to understand what's actually going wrong. Here are the most common causes:
Data roaming is turned off. Travel eSIMs connect through local partner networks abroad, which your phone classifies as roaming. If roaming is disabled, your eSIM will show a signal but won't load data.
The eSIM isn't set as your primary data line. On dual-SIM devices, your phone may default to your physical SIM for mobile data. Your eSIM stays inactive until you switch it over manually.
Incorrect or missing APN settings. The APN (Access Point Name) tells your device how to connect to the mobile network. If it's blank or wrong, data won't work even if your eSIM appears active.
The eSIM profile didn't install properly. A weak Wi-Fi connection during setup, a failed QR code scan, or an interrupted download can leave your profile incomplete.
Your device is carrier-locked. Some phones only work with their original carrier's SIM cards. A carrier lock will prevent any eSIM from a different provider from activating.
Outdated software. Older iOS or Android versions can cause eSIM compatibility problems that a simple update will fix.
Weak or unavailable network signal. Poor coverage in remote areas, underground spaces, or directly after landing can cause a temporary connection failure. Usually resolves on its own within a few minutes.
Get Support for your KnowRoaming eSIM Here
How to Fix Your eSIM: 10 Step-by-Step Solutions
1. Turn on Data Roaming
This is the fix that solves the majority of travel eSIM issues. Most eSIM plans use local carrier networks abroad, and your phone needs data roaming enabled to access them.
iPhone:
- Open Settings
- Tap Cellular (or Mobile Data)
- Select your eSIM line
- Toggle Data Roaming on
Android:
- Open Settings
- Tap Connections, then Mobile Networks
- Select your eSIM
- Toggle Data Roaming on
After enabling roaming, toggle Airplane Mode on and off to force your phone to reconnect.
2. Set Your eSIM as the Primary Data Line
On dual-SIM devices, your phone may be sending data through your physical SIM instead of your eSIM.
iPhone:
- Open Settings
- Tap Cellular (or Mobile Data)
- Tap Cellular Data
- Select your eSIM from the list
Android:
- Open Settings
- Tap Connections, then SIM Manager
- Under Mobile Data, select your eSIM
3. Toggle Airplane Mode
A quick airplane mode reset forces your device to drop its current network connection and find a new one. It only takes 15 seconds and fixes many connection glitches.
iPhone: Settings > Airplane Mode > On > wait 15 seconds > Off
Android: Settings > Connections > Airplane Mode > On > wait 15 seconds > Off
4. Check Your eSIM Is Installed Correctly
If your eSIM profile didn't finish installing, your device won't be able to connect at all.
iPhone:
- Open Settings
- Tap Cellular (or Mobile Data)
- Look for your eSIM under SIMs or Cellular Plans
- If it's missing, tap Add eSIM and reinstall using your QR code
Android:
- Open Settings
- Tap Connections, then SIM Manager
- Check that your eSIM profile appears
- If it's missing, tap Add eSIM and scan your QR code again
Important: Do not delete your eSIM profile unless instructed by support. Many eSIM QR codes can only be used once. If yours is missing but the QR has already been scanned, contact your provider to request a new one.
5. Check and Update APN Settings
APN settings tell your device how to connect to the mobile data network. Most eSIMs configure these automatically, but in some cases you may need to set them manually.
iPhone:
- Open Settings
- Tap Cellular (or Mobile Data)
- Select your eSIM line
- Tap Cellular Data Network
- Enter the APN details provided by your eSIM provider
Android:
- Open Settings
- Tap Connections, then Mobile Networks
- Tap Access Point Names (APN)
- Add or edit the APN using the details from your provider
For KnowRoaming, your APN details are available in the KnowRoaming app and in your activation email. If you're unsure what to enter, our 24/7 support team can walk you through it.
6. Restart Your Device
Simple but effective. A restart clears temporary network glitches and forces your device to re-register with available networks.
iPhone: Hold the side button and volume button > slide to power off > wait 10 seconds > turn back on
Android: Hold the power button > tap Restart or Reboot
7. Update Your Device Software
Outdated iOS or Android versions can cause eSIM compatibility issues. Always check for updates when you're troubleshooting.
iPhone:
- Open Settings
- Tap General
- Tap Software Update
- Install any available updates
Android:
- Open Settings
- Tap Software Update
- Download and install available updates
8. Switch from 5G to LTE
5G roaming is not supported in all countries. If your phone is trying to connect to a 5G network that isn't available in your destination, switching to LTE can restore your data connection immediately.
iPhone:
- Open Settings
- Tap Cellular, then select your eSIM line
- Tap Voice and Data
- Select LTE
Android:
- Open Settings
- Tap Connections, then Mobile Networks
- Tap Network Mode
- Select LTE or 4G
9. Check for a Carrier Lock
A carrier lock means your phone is restricted to one specific network. If your device is locked, it won't be able to activate an eSIM from another provider.
iPhone:
- Open Settings
- Tap General, then About
- Look for Carrier Lock
- If it says "No SIM restrictions," your phone is unlocked
Android: The process varies by brand. The quickest way is to contact your original carrier and ask them to confirm whether your device is locked.
If your phone is carrier-locked, you'll need to contact your carrier to unlock it before your eSIM will work. Most carriers will unlock your device after your contract period ends or if you've paid off the device in full.
10. Reset Network Settings
If nothing else has worked, resetting your network settings clears misconfigured data that might be blocking your connection. Note: this will remove saved Wi-Fi passwords and Bluetooth connections.
iPhone:
- Open Settings
- Tap General
- Tap Transfer or Reset iPhone
- Tap Reset, then Reset Network Settings
Android:
- Open Settings
- Tap General Management
- Tap Reset
- Select Reset Network Settings and confirm
After the reset, reinstall your eSIM and go through the setup steps again.
Why Is My KnowRoaming eSIM Not Working?
If you're using a KnowRoaming eSIM and still having trouble after working through the steps above, here are a few KnowRoaming-specific things to check.
Check your data balance. If your plan has expired or your data has run out, your eSIM will stop working. You can check your remaining data and top up directly in the KnowRoaming app.
Confirm your destination is covered. KnowRoaming eSIMs work in 200+ destinations worldwide, but coverage can vary by plan. Check the coverage map in the app to confirm your destination is supported.
Make sure your eSIM was activated before departure. KnowRoaming eSIMs need to be installed and activated on Wi-Fi before you travel. If you haven't activated yet, do so through the KnowRoaming app before leaving home.
Verify your APN is set correctly. Your APN details are included in your activation email and available in the KnowRoaming app. If data still isn't loading after enabling roaming, manually entering the APN is often the fastest fix.
If you've checked all of this and your KnowRoaming eSIM still isn't working, our 24/7 support team is available to help. Reach us through the KnowRoaming app or at support@knowroaming.com.
Frequently Asked Questions
Why does my eSIM show signal but no data? The most common cause is that data roaming is turned off. Enable roaming in your cellular settings, then toggle Airplane Mode on and off. If that doesn't work, check your APN settings, as these may need to be entered manually.
Why is my eSIM not working on my iPhone? On iPhone, the most common causes are data roaming being off, the eSIM not being selected as the active data line, or incorrect APN settings. Go to Settings > Cellular > select your eSIM line > enable Data Roaming > set as default for cellular data.
What does "No Service" mean on an eSIM? "No Service" usually means your device can't register with the local network. This can be caused by roaming being disabled, weak signal coverage, a carrier lock, or an incomplete eSIM installation. Work through the fixes above starting with enabling data roaming.
Can I use my eSIM in airplane mode? No. Airplane mode disables all cellular connections, including your eSIM. You can use Wi-Fi calling on some devices while in airplane mode, but standard mobile data requires airplane mode to be off.
Why is my eSIM not working after I reinstalled it? If you deleted your eSIM and reinstalled it, the issue may be related to your QR code being single-use. Contact your eSIM provider to get a new QR code or activation link. Once reinstalled, make sure data roaming is on and your eSIM is selected as the primary data line.
Do I need to activate my KnowRoaming eSIM before I travel? Yes. KnowRoaming eSIMs must be installed on a Wi-Fi connection before you leave home. Installation requires downloading the profile, which needs an internet connection.
Still Stuck? KnowRoaming 24/7 Support Is Here
eSIM not working issues are almost always solvable, and the fixes above resolve the vast majority of cases. But if you've worked through every step and still can't connect, our support team is available 24/7 to help diagnose the issue.
KnowRoaming eSIMs work in 200+ destinations, with regional and global plans available for purchase and instant installation through the KnowRoaming app. No roaming fees, no physical SIM swaps, and real support when you need it.