If your iPhone SE 4 isn't ringing or showing missed calls, you're missing important connections. This is a common but fixable problem on iOS 18. I'd start with the simplest checks first, as a quick setting toggle often does the trick.
The most common fix is to check your Focus modes. Swipe down from the top-right corner to open Control Center and look for the Focus icon. If it's highlighted, tap it to turn it off. You can also go to Settings > Focus and make sure no active Focus is silencing calls from the people you want to hear from.
Check Your Cellular Connection and Signal
First, look at the signal bars in the top-right corner of your screen. If you see "No Service" or just one bar, you might be in a dead zone. Try moving to a different location or going near a window. Toggle Airplane Mode on and off to force a network reconnection. You can do this quickly from Control Center by tapping the airplane icon.
Next, verify your cellular data is active. Go to Settings > Cellular and make sure the Cellular Data switch is on. While you're there, tap Cellular Data Options and ensure Voice & Data is set to "5G Auto" or "LTE" for the best call reliability.
Review Do Not Disturb and Silence Unknown Callers
Beyond the standard Focus modes, there are specific call-silencing settings to check. Head to Settings > Phone. Scroll down and look for Silence Unknown Callers. If this is enabled, calls from numbers not in your contacts, Mail, or Messages will be sent directly to voicemail without ringing.
Also, check your Do Not Disturb schedule. Go to Settings > Focus > Do Not Disturb. Look under the "Schedule" section to see if a specific time window is automatically activating. You can adjust who is allowed to break through by tapping "People" and ensuring key contacts are added.
Investigate Call Forwarding and Blocked Contacts
It's possible your calls are being forwarded to another number without you realizing it. To check, open the Phone app and tap the Keypad tab. Dial #21# and then tap the call button. This will show you if any unconditional call forwarding is active on your line.
You should also review your blocked numbers list. Go to Settings > Phone > Blocked Contacts. If someone you're expecting calls from appears here, swipe left on their name and tap "Unblock."
Update iOS and Restart Your iPhone SE 4
Software bugs in iOS 18 can sometimes affect call functionality. Make sure your iPhone SE 4 is running the latest version. Go to Settings > General > Software Update. If an update is available, install it. It's a good practice to keep Optimized Battery Charging enabled in your battery settings, as it helps maintain overall system health.
If the problem persists, perform a force restart. This clears the device's memory without deleting any data. On the iPhone SE 4, quickly press and release the Volume Up button, then quickly press and release the Volume Down button. Finally, press and hold the Side button until you see the Apple logo appear, then release.
Reset Network Settings and Check the SIM
Corrupted network settings can prevent your phone from registering on the network properly. Go to Settings > General > Transfer or Reset iPhone > Reset. Choose Reset Network Settings. This will erase all saved Wi-Fi passwords and Bluetooth pairings, so you'll need to reconnect to your networks afterward.
For a physical check, locate the SIM tray on the left side of your iPhone SE 4. Use the SIM eject tool (or a small paperclip) to open the tray. Remove the SIM card, inspect it for any visible damage or dirt, and then firmly reinsert it. If you have access to another compatible phone, you can test the SIM card in it to rule out a faulty card.
Contact Your Carrier
If you've tried everything and calls still aren't coming through, the issue may be with your carrier account. There could be a network outage in your area, a problem with your specific line, or a feature like Call Forwarding that was activated on the network side. Use another phone to call your carrier's customer service.
You can also ask them to reprovision your line, which refreshes your connection to their network. They can also verify there are no account blocks or unpaid bills preventing service. Since the iPhone SE 4 uses a standard USB-C port and supports modern networks, hardware incompatibility is rarely the cause.
