I didn’t see the option to choose 3G, only an option to turn off LTE. When I turned off LTE the phone defaulted to 4G. This was in Cellular options menu in settings. I didn’t see anything useful in the carrier menu either. Regardless, it still doesn’t work over cellular anymore. I usually use Android and I know how to force 3G on my Samsung but I don’t see that option in iOS. It’s working fine on the Samsung.