How To Change Network Mode on Samsung Galaxy

To change Network Mode you can follow this steps:
Open Settings - More networks - Mobile networks. Then select Network mode, if you have 2 SIM cards on your device, chose SIM that you want to change the netword mode.
There is 3 options: WCDMA/GSM, WCDMA only and GSM only. WCDMA (3G) network mode it better than GSM, I suggest you to select WCDMA only is possible.

How to change network mode on Android 7 Nougat: https://youtu.be/pd6JNU_EnMM

Видео How To Change Network Mode on Samsung Galaxy канала AndroidHowTo