Users with locked Xiaomi phones simply need to activate a Wi-Fi connection to unblock their device .
Read moreHow do I activate LTE on my mi phone?
Select Settings
Read moreHow do I change my Xiaomi network 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.
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