Hi Jagwaran, welcome to the forum What type of account do you have with ATT?? Remember the 3G and the 4G LTE service sometimes is not available in all areas, it depends on the coverage. Another reason why you see the letter E for 2G is the APN's that are on the settings of the phone, if your device is LTE capable you will need to edit the APN's on the device, of course you can give us a call by dialing 611 from your device.
Thank You Manuel
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