add 3g only in miui menu

Why would you want it to be 3G only? If you ever have no 3G signal then your phone will not be able to recieve any calls/texts.

Unless I’m mistaken 3g is also known as WCDMA. If you type *#*#INFO#*#* and click onto “Phone Information”. Scroll down and you’ll see a dropbox which says “WCDMA prefererred”. Change that to “WCDMA only” and there you go. Your phone is now 3g only.

I prefer “WCDMA preffered” that way the phone will stay on 3G unless there is no 3G signal. Then it will switch to 2G until a 3G signal can be found.