Check your apn's should be
And the last few lines will default to correct settings. But that's listed in order top to bottom. Except the last few lines that will default like I said. Check those if they're correct then may be an antenna issue. I got a moto RAZR one time that wouldn't connect to 4g and it was the internal antenna. They sent out a new one over night. No argue no issue. The new one worked great.
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