Can't flash TWRP after unlocking the phone

[BloodScar36]

Hey guys.
After hours of trying to unlock my Mi Mix 2 I've finally finished the process, even the options say that my bootloader is unlocked. Now I wanted to flash TWRP on it, downloaded the image and used the 'fastboot flash recovery imagename' command. But I can't see any progress, the command line is just empty. I searched the XDA forums and other sites, reinstalled the fastboot driver (the device is shown with 'fastboot devices') restarted the phone over and over again. I don't know what else to do. I tried Porwershell and cmd, but everytime the command line is empty and stays so.
Also, the TWRP App says that my phone isn't rooted, could there have been problems with unlocking the Mi Mix 2?

 

[elig99]

Also, the TWRP App says that my phone isn't rooted, could there have been problems with unlocking the Mi Mix 2?

Bootloader unlocking does not additionally root your phone, thus there is no problem with the indication mentioned above.

 

[slaihk]

Bootloader unlocking does not additionally root your phone, thus there is no problem with the indication mentioned above.

Hello, you should first boot, not flash, the twrp img and get your device into twrp. Then flash the twrp within the twrp app.
This should do.

 

[katerpanne]

# fastboot boot twrp.img
if you flash the rom twrp will be persistent