Yeah I was able to fix the problem by using the cingular apn setting, but that was on the 55 firmware, I updated to the 69 firmware and the default at&t apn settings that you can download to the phone worked. I have a D6503.
I am on ATT, I don't get the LTE icon, only 4G symbol, speed seems fine, but no LTE icon, APN setting was set when I download the MMS setting,
for those Z2 users on ATT, do you have LTE icon on your phone ?
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