Seeing that "No SIM" message on your Nothing Phone (2) is a real buzzkill. You can't make calls, send texts, or use mobile data, which defeats the purpose of having this sleek device. The good news is this is almost always a simple fix you can handle yourself.
I'd start with the basics, as they solve the majority of these issues in under a minute.
Restart Your Phone and Check Airplane Mode
First, give your Phone (2) a fresh start. Press and hold the power button until the power menu appears, then tap "Restart." If the phone is completely frozen, you can force restart it by holding the power button for about 10 seconds until it vibrates and reboots.
Next, swipe down from the top of your screen twice to open the full Quick Settings panel. Look for the airplane icon and tap it to turn Airplane Mode on. Wait about 10 seconds, then tap it again to turn it off. This forces the phone's modem to reconnect to the network from scratch.
Verify the SIM is Enabled in Settings
Sometimes, a software hiccup can make the phone think the SIM is disabled. Open your Settings app and go to Network & internet > SIMs. Here, you should see your SIM card listed. Make sure the toggle next to it is switched on.
While you're in this menu, also check that the "Mobile data" option is enabled for that SIM. If you see an option for "Preferred network type," set it to "5G/4G/3G/2G (auto)" to let the phone find the best available signal.
Inspect and Clean the Physical SIM Card
If the software checks out, the next step is to look at the SIM card itself. Power your phone off completely. Find the SIM ejector tool that came in the box (a paperclip works in a pinch) and gently push it into the small hole on the SIM tray, which is on the bottom edge of the Phone (2).
Carefully pull the tray out and remove the SIM card. Look closely at the gold-colored contacts on the chip. If you see any dust, lint, or a faint oily film, that's likely the culprit. Gently wipe the contacts with a clean, dry microfiber cloth.
Also, peek into the empty SIM slot on the phone. Use a can of compressed air to blow out any dust that might have settled in there. Reinsert the SIM card, making sure it's seated correctly in the tray, and slide the tray back in until it clicks.
Test the SIM in Another Device
This is the best way to figure out if the problem is with your SIM card or with the phone itself. Take your SIM card and put it into another unlocked phone. If that other phone also says "No SIM," then you know the issue is with the card or your carrier account.
In that case, you'll need to contact your mobile provider. They can check if your line is active and, if needed, send you a replacement SIM card, which usually solves it. If the SIM works perfectly in another phone, then the issue is localized to your Nothing Phone (2).
Update Nothing OS
Software bugs can occasionally interfere with the modem or SIM detection. Nothing is pretty good about pushing out fixes. To check, go to Settings > System > System update.
Tap "Check for update." If an update is available, download and install it. It's a good idea to be connected to Wi-Fi for this. After the update finishes, your phone will restart, which often clears up minor glitches.
Reset Your Network Settings
This is a more thorough step that clears all your saved network configurations without touching your personal photos, apps, or messages. It will erase your Wi-Fi passwords, paired Bluetooth devices, and mobile network settings.
To do it, navigate to Settings > System > Reset options. Here, tap on "Reset Wi-Fi, mobile & Bluetooth." Confirm your choice, and the phone will reboot. After it comes back on, you'll need to re-enter your Wi-Fi password and re-pair Bluetooth devices, but it can work wonders for persistent network issues.
Check and Reset APN Settings
The Access Point Name (APN) is like the address your phone uses to connect to your carrier's internet. If these settings are wrong, you might see a "No SIM" or "Emergency calls only" message. Go to Settings > Network & internet > SIMs > Access Point Names.
You should see a list of APNs. If your carrier's correct APN is already there, make sure it is selected (there will be a filled-in circle next to it). If the settings look wrong or are missing, you'll need to input them manually. You can get the correct APN details from your carrier's website or customer service.
If you're unsure, you can try resetting them to default. Tap the three-dot menu in the top right and select "Reset to default."
Try Manual Network Selection
By default, your phone automatically connects to your carrier's network. Sometimes this process can get stuck. You can force it to search again manually. Go to Settings > Network & internet > SIMs.
Look for an option called "Network operators" or "Carrier." Tap it, and the phone will start searching. When the list pops up, select your carrier's name from it. This tells the phone to explicitly connect to that network instead of trying to figure it out automatically.
Consider Switching to eSIM
The Nothing Phone (2) supports eSIM, which is a digital SIM embedded in the phone. If your physical SIM tray or reader is having a hardware issue, or if your physical SIM card is old and flaky, moving to an eSIM can be a permanent solution.
You'll need to contact your carrier to see if they support eSIM activation and to get a QR code to scan. The process to set it up is in Settings > Network & internet > SIMs > Add eSIM. This bypasses the physical SIM hardware entirely.
Perform a Factory Reset
This is the last resort for software-related problems. A factory reset will erase everything on your phone and return it to its original out-of-the-box state. You must back up all your important data, photos, and messages before proceeding.
To back up, use Google One or your preferred method. Once backed up, go to Settings > System > Reset options > Erase all data (factory reset). Follow the prompts to confirm. After the reset, you can set the phone up as new to test the SIM, or restore your backup.