No longer receiving LTE signals
I have been using my iPhone 6s on ATT gophone for two months now. Recently I have noticed I do not get LTE in areas I did (school, work, interstate). It seems the only place I get LTE is at my house (1 bar). My friend has an iPhone 6s as well that is running on ATT postpaid and they have LTE in the same places I only have 4G. Just an example: I had 4 bars of 4G and my friend had 5 bars of LTE. I know another friend who uses an MVNO on att towers that gets LTE where I don't. Why all of a sudden I no longer have LTE? Should I try to get a new gophone sim card? My iphone 6s has all the bands required by att since I bought it straight from apple, unlocked. I looked at the coverage map, to see that I should have LTE, and it had an asterisk saying that 4G LTE data supported by gophone. I also made sure that my phone settings says LTE for data and voice. I don't know if this matters, I've used field testing on the iPhone at home and I've notcied that my iPhone keeps switching back and forth from band 2 and band 12 on LTE. I can't check the bands when I have 4G.