Seeing calls drop or fail on your Nothing Phone 2a can be a real headache, especially when you're trying to connect with someone. This usually happens when your phone can't maintain a stable link to your carrier's network. Weak signal, a software hiccup in Nothing OS, or a misconfigured setting are the most likely culprits.
Let's run through the most effective fixes, starting with the quick ones you can do in under a minute.
Toggle Airplane Mode On and Off
This is the fastest way to refresh your cellular connection. It forces your Phone 2a to disconnect from the network and reconnect, which can clear up temporary glitches.
Swipe down from the top of your screen to open the Quick Settings panel. Tap the Airplane Mode icon to turn it on. Wait about 10 seconds, then tap it again to turn it off. You should see the signal bars search and reconnect.
Check Your Signal Strength
Weak signal is the number one reason for call failures. Look at the signal bars in the top-right corner of your screen. If you have one bar or see an "X," you're in a poor coverage area.
Try moving to a different spot, preferably near a window or outside. Buildings, walls, and even weather can significantly impact your Nothing Phone 2a's ability to hold a call.
Perform a Force Restart
If a simple toggle didn't work, a full restart can clear out any stuck software processes. For the Nothing Phone 2a, press and hold the Power button for 10 to 15 seconds.
Keep holding it until you see the screen go black and the Nothing logo reappear. This is a soft reset and won't delete any of your data or settings.
Verify Your Focus Mode Settings
Nothing OS includes Focus modes that can silence notifications and calls. It's possible you've accidentally set a rule that's blocking incoming calls.
Swipe down from the top and check the Quick Settings for an active Focus icon (like a moon). You can also go to Settings > Digital Wellbeing & parental controls > Focus modes to see which profiles are active and adjust their rules.
Check for Blocked Numbers
Make sure you haven't accidentally blocked the person you're trying to call, or that their calls aren't being blocked. The Phone app has its own blocking list.
Open your Phone app, tap the three-dot menu in the top-right, and go to Settings > Blocked numbers. Review the list and remove any numbers that shouldn't be there.
Ensure Cellular Data is Enabled
While calls use the voice network, some carrier services (like HD Voice or VoLTE) rely on cellular data being active. It's a good setting to double-check.
Head to Settings > Network & internet > SIMs. Select your active SIM card and make sure the "Mobile data" toggle is switched on. If you're traveling, you may also need to enable "Data roaming" within the same menu, but be aware of potential charges.
Update Your Carrier Settings
Sometimes your carrier pushes small configuration updates to improve network connectivity. These can happen automatically, but it's worth checking.
Connect your Phone 2a to Wi-Fi first. Then, go to Settings > System > System update. Tap the gear icon in the top-right and select "Update profile." If an update is available, follow the prompts to install it.
Try Switching Network Mode
In areas with spotty 4G/5G coverage, forcing your phone to use an older, more stable network type like 3G can help calls connect. This is a good temporary test.
Go to Settings > Network & internet > SIMs. Tap your SIM, then Preferred network type. Try selecting "3G" instead of "5G/4G/3G." Make a test call, then switch the setting back afterward.
Inspect and Re-seat Your SIM Card
A loose, dirty, or faulty SIM card is a classic cause of network issues. The SIM tray on the Phone 2a is on the bottom edge.
Use the SIM eject tool that came with your phone (or a small paperclip) to pop out the tray. Remove the SIM card, gently wipe the gold contacts with a soft, dry cloth, and carefully reinsert it. Make sure it's seated flush in the tray before pushing it back into the phone.
Update Nothing OS
Software updates from Nothing often include bug fixes for connectivity and calling problems. Keeping your Phone 2a updated is one of the best ways to prevent issues.
Plug your phone in or ensure it has over 50% battery, then connect to Wi-Fi. Navigate to Settings > System > System update. If an update is listed, download and install it. Your phone will restart as part of the process.
Reset Your Network Settings
This is a more thorough step that clears all saved Wi-Fi networks, Bluetooth pairings, and cellular network preferences. It doesn't erase your apps or personal files.
Go to Settings > System > Reset options. Tap Reset Wi-Fi, mobile & Bluetooth. You'll need to enter your lock screen PIN or password to confirm. After the reset, you'll have to reconnect to Wi-Fi and re-pair Bluetooth devices.
Contact Your Mobile Carrier
If you've tried everything here and calls are still failing, the problem might be on your carrier's end. There could be a local network outage, a problem with your account, or your SIM card itself might need replacing.
Give your carrier's customer service a call from another phone if possible. Ask them to check for outages and verify your line is provisioned correctly for voice services. They can also perform remote diagnostics and send you a new SIM card if needed.