Fasboot Devices not getting attached XIAOMI MI A3

I have the *Xiaomi Mi A3* and I'm currently on both phone and PC latest stock update. I am using Windows 10 20H2 and I have tried everything – but still don't get it. I tried another Mi A3 and it got attached normally. I've tried installing all kind of drivers and different ports, nothing. When suddenly it worked and I installed the stock ROM – but because the stock ROM is kinda laggy and ugly I want to change it. But I can't because I am also on stock recovery and I can't install another recovery because my device isn't recognized in fastboot mode. My device is recognized in adb mode and in edl mode as well, only not in fastboot.