Originally Posted by
Cincybearcatfan I don't mean to assume but If you're on build E then it should be turned on by default. On build D it has to be manually setup. Also make sure you add the feature to both handsets on your Verizon account via the website.
If for some reason the HD Voice Calling option is disabled or inaccessible on your phone after updating to Android 5.1, then you can try the following steps to fix the issue.
Navigate to Settings > More > Cellular Networks and enable the toggle switch for Enhanced 4G LTE Mode. However, if the toggle is missing then follow the steps provided below:
Launch the Dialer app on your phone, and dial *#*#4636#*#*.
Choose Phone information.
Enable or select VoLTE Provisioned Flag.
Restart the phone.
Go to Settings " More " Cellular networks and toggle the switch for Enhanced 4G LTE Mode, and the HD Voice calling feature should now be activated on your device running Android 5.1.