Update your phone's operating system and firmware. If your phone can accept VoLTE functionality, the update will install it.
If you have been affected by the 3G shutdown: The 3G shutdown affects all phones that are not VoLTE-capable. Most phones that have 4G or 5G access will also have VoLTE functionality, but first, a software update may be necessary.
A software update can improve the way your phone operates. It can fix bugs or security problems that have been identified by the device manufacturer or your wireless carrier. It can
Follow the steps below to see if your phone requires a software update.
1A: Update your software (Android)
As a precaution, back up your device's data. Connect your phone to its charger. It's best to complete a backup and an update while your device is plugged in and charging.
Step 1: Tap on your phone's Settings.
Step 2: Tap on "About Phone".
Step 3: Tap on the "Check Updates" button and wait to see if you have any available software updates for your phone. If not, you'll see a message that lets you know your phone is up to date.
Step 4: Download and install any available updates.
Important!
Now is a good time to try and use your device. If your phone is still not working, then continue troubleshooting. Always test your device functionality after each troubleshooting step.
1B: Update your software (iOS)
As a precaution, back up your device's data. Connect your phone to its charger. It's best to complete a backup and an update while your device is plugged in and charging.