How to fix your HTC U12/U12 Plus that can’t make or receive phone calls [Troubleshooting Guide]

Calling and texting are basic yet the very core functions of a mobile phone. Even contemporary smartphones are designed to serve such purpose. That’s why it matters to every cell phone or smartphone owner if calling problems occur. This is usually what you will bump into if your phone is experiencing network connectivity errors from on and off signal to no signal at all. Even the latest powerful Android smartphones are no exemption.

To give you some inputs on how to deal with calling issues, I’ve lined out some simple solutions to try. These methods however specifically apply to an HTC U12/U12 Plus smartphone. Feel free to try any of these given workarounds if all of a sudden, you cannot make or receive phone calls on your new HTC smartphone.

If you have other problems however, visit our troubleshooting page as we’ve already addressed some of the most common issues with this device. Browse through the page to find issues that are similar with yours and feel free to use the solutions we suggested. If you still need our help, fill up our questionnaire and hit submit to contact us.

How to troubleshoot HTC U12 that can’t make or receive phone calls

Before you troubleshoot your device, check and ensure that there is no ongoing network outage affecting network-related services in your area. If all your devices aren’t able to make and receive phone calls, then it’s likely due to an outage. In that case, you don’t need to troubleshoot because the problem is not on your end and that should be taken care of by your network service provider.

First solution: Reboot your phone (soft reset).

Minor software issues on the phone may have affected or messed up its calling functions. The simplest solution to try first is a soft reset or system restart. It effectively dumps cache and erratic temporary files from the internal memory including those that that caused network conflicts. To soft reset your HTC U12/U12 Plus, just follow these steps:

1. Press and hold down the Power button for a few seconds.
2. Select Power off from the menu options then tap OK to turn off your phone.
3. After 30 seconds, press and hold the Power button again until the phone restarts.

Wait until your phone is finished rebooting and then make a test call to your own number and see if you can receive it already.

Second solution: Boot your phone in safe mode and do a test call.

To rule out errant applications among the possible triggers, try to boot your HTC U12/U12 Plus in safe mode and then diagnose your apps. All third-party apps and services are temporarily disabled or bypassed in safe mode, thus leaving only the pre-installed applications. This therefore makes it easier for you to determine whether or not a third-party app is to blame. Here’s how to enable safe mode on this HTC device:

1. Press and hold the Power button for a few seconds until the menu options show up.
2. Then tap and hold Power off option. Your phone will restart and you should see Safe Mode at the lower portion of the screen.

You can also restart your phone in safe mode using the hardware keys. Here’s how it’s done:

1. Press the Power button to turn on your phone.
2. As soon as you see the HTC logo on the screen, press and hold the Volume Down button until you see Safe Mode at the lower portion of the screen.

Try to make a test call while your phone runs in safe mode. If it’s able to make or receive the call, then your next challenge is to identify which from your downloaded apps is the culprit. Try to think of which app you’ve downloaded recently before the problem started. You may have to uninstall individual apps starting from your most recent download.

If the problem continues even when your phone is in safe mode, then the problem could be attributed to a fatal system error, if not hardware damage on the phone.

Third solution: Toggle Airplane Mode on and off again.

Another trick that effectively deals with random network errors on an Android smartphone is the Airplane mode trick. It has already done a lot of wonder to many smartphone owners who have dealt with various types of software issues including calling problems. Should this be just a random glitch on the phone’s network system, then performing this trick can potentially fix it. Here’s what you should do then:

1. Go to Settings.
2. Tap Network & Internet.
3. Tap the Airplane mode switch to turn the feature on for a few seconds and then tap to turn it off again.
4. Or you can also swipe your two fingers down from the status bar to launch the Quick Settings panel. Then, tap the Airplane Mode icon to turn feature on and then off again shortly.

This old trick is also an alternative way to restart and refresh wireless features and network functions on the phone. You will know when Airplane Mode is turned if you see the airplane icon in the status bar. Be sure to turn the feature off again to use network features on your phone.

Fourth solution: Reset network settings.

Incorrect network configuration on the phone can also lead to this problem. You can consider network settings errors as the underlying cause if your phone suddenly failed to make or receive phone calls are modifying some settings and options. The same thing can happen after installing an update that’s programmed to override current network settings on the receiving device. To rectify the errors, try to reset network settings on your HTC U12/U12 Plus with these steps:

1. Swipe up from the Home screen.
2. Tap Settings.
3. Tap System.
4. Select Reset to continue.
5. Tap Network settings reset from the given options.
6. Tap RESET SETTINGS.
7. Then confirm reset by tapping on Reset settings again.

Your phone will then start clearing the network settings and then restore the default options or original configuration. To ensure that changes are properly implemented, reboot your phone and then manually enable network features on the phone including Wi-Fi or cellular network.

Fifth solution: Remove then reinstall your SIM card.

If the problem isn’t tied to a software error, then it’s likely hardware-related. To get started with hardware fixing, work on your SIM card. Your phone won’t be able to perform network functions if the SIM card is defective or dislodged from the tray. In that case, removing and reinstalling the SIM card on your HTC U12/U12 Plus can help. Here’s how it’s done:

1. Turn off your phone completely.
2. Position your phone face up.
3. Insert the tray eject tool or a small bent paperclip into the provided tray eject hole. Be sure not to obstruct the tray when inserting the eject tool into the tray eject hole to prevent causing damage to the eject mechanism inside the slot.
4. Gently push the tip all the way into the hole until the SIM tray ejects.
5. Then pull the tray out.
6. Remove the SIM card from the card slot and check for any visible signs of damage. If everything looks good with the card, place it back into the card slot with the gold contacts facing down.
7. If necessary, place your microSD card into its designated slot of the tray. Be sure to align the cut-off corner of the nano SIM card to the notch of the holder to secure it.
8. When the SIM and SD cards are secured, reinsert the tray into the tray slot. Make sure it’s facing up so that the cards won’t fall out.
9. Steadily slide the tray all the way into the slot until the tray is fully inserted and doesn’t protrude from the slot.

Once the SIM card tray locked and secured in place, turn on your phone and do a test call. Make sure that the signal indicator shows some stable bars (at least 2 bars) before you make a test call. If the signal indicator shows nothing or pertinent errors, then that’s what you need to deal with first. Contact your network service provider to report the problem and request more help in fixing it. Once the signal is restored, calling, texting and other network-related operations should be back up and running smoothly again.

Other options

If your HTC U12/U12 Plus still cannot make or receive phone calls after carrying out all prior methods, then you may consider performing a factory data reset to clear out major system errors that might have corrupted the phone’s network system and caused it to fail. This however will wipe all important data from your phone, thus creating a backups is recommended.

Taking your phone to an HTC-authorized service center can also be considered among the last options, if the problem continues even after performing a factory data reset. Your device might have obtained some sort of physical or liquid damage and therefore requires service.

For further troubleshooting assistance and recommendations, you may contact your network service provider or HTC Support team to escalate the problem.

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