Go to Settings > Cellular > Cellular Data Options . If you see this screen, your device has 5G activated.
Read moreWhy is my phone not using my 5G?
Check with your carrier to make sure you have the correct data plan. Also, make sure you are using the SIM card that came with your phone or a 5G compatible SIM provided by your carrier. Older SIM cards may not be compatible with 5G plans. You can check Network mode to make sure that your phone has 5G enabled.
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