My Galaxy S4/S4 mini should be 4G but says it's 3G. Why?
Are you in a 4G area? If so, you could try resetting your SIM card by turning off the phone, removing the SIM card (be careful not to touch the gold contacts), waiting a minute or so, then reinserting the card, turning the phone back on, and allowing time for a fresh network connection to be established.
