If changes or degradation in voice call quality after updating to iOS 12.1.1, you may need to change a Cellular Setting. This change will only need to be made if the following conditions are met:
Have updated iPhone to software version 12.1.1 or above
o Confirm under Settings > General > About > Version
Has or had Wi-Fi Calling enabled
o Confirm under Settings > Cellular > Wi-Fi Calling – If the user has it turned off, but has enabled the service previously, then flipping the toggle back on will display an “Enable Wi-Fi Calling? > Enable” pop-up with no further actions required.
Enable LTE menu is set to Voice & Data
o Confirm under Settings > Cellular > Cellular Data Options > Enable LTE > Voice & Data
If you do not meet any of these conditions, continue with normal troubleshooting.
If you experience changes or degradation in voice call quality after updating to iOS 12.1.1 and its confirmed that you previously enabled/used Wi-Fi Calling, then go through the following setting change:
Settings > Cellular > Cellular Data Options > Enable LTE > Change to Data Only
Some users may not see the "Phone is Activated" pop-up message after walking through the Out-of-Box-Experience/set-up. The activation may happen prior to set-up being completed and the "Phone is Activated" message can pop up behind the set-up screens.
To verify activation, users can look for the LTE indicator in the upper right-hand corner of the screen, pull down the control panel and look for Sprint in the upper left, or users can simply attempt a phone call to confirm activation.
Sprint and Apple are aware of this issue and working to resolve.
Impacts: All 2018 iPhones. This should not impact the iWatch 4 series.
The device will display No Service in the following countries until those carriers implement the new USASV IMSI range in their network elements.
Sprint is working with our roaming partners to implement the new IMSI range in their networks to resolve this issue. Current list of impacted countries include:
Gulf of Mexico
India (part of country ready)