If you don’t see 5G in the status bar Go to Settings > Cellular > Cellular Data Options. If you see this screen, your device has 5G activated. If you don’t see this screen, contact your carrier to confirm that your plan supports 5G . Turn on Airplane Mode, then turn it off.
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In particular, try resetting the network settings . As the page notes, “Tap Settings > General > Reset > Reset Network Settings. This also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you’ve used before.” Be sure to also note down any needed Wi-Fi passwords ahead of this step.
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