Choose Phone > Read from phone > UMTS System . This will show which 3G bands are currently enabled. Add checkmarks to the additional 3G bands that you would like to add.
Read moreHow do you lock a mobile band?
See steps for Android 8.1 and below.
Read moreHow do I lock my LTE network to band 40?
Method 1: Lock the 4G network to Jio Band 40
Read moreHow do I change the frequency of my xiaomi band?
Settings> About Phone> Tap 5 times on internal memory> Now you are in Testing menu> Select the Phone information1 for SIM 1 or Phone information2 for SIM 2> Scroll down to find Set preferred network type and select it> From the list select the one you want and go back to home.
Read moreDoes redmi Note 8 support 4G+?
It has 4G+ with B3 + B20 CA .
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