XiaomiToolV2

Try this one: https://github.com/topminipie/XiaoMiToolV2 
 
 Or This: https://androidmtk.com/xiaomitool-v2 
 
 Solution 
 https://github.com/topminipie/awesome-xiaomi-bootloader-unlock#miunlocktool--mibypasstool--mitool 
 Download this: https://github.com/offici5l/MiUnlockTool 
 One device per Mi account per Month