Thank you all for your help and replies. i will try to explain what the situation is:
- Developer options are there, I can see i.e. USB debugging etc., but nothing related to Mi unlock status.
- Using the updater app, there is no update
- Using the updater app, I can choose a ROM which I dowloaded from Miui, but my phone tells me with every ROM that it can not be verified.
- Switching to bootloader and using XiaoMiFlash, flashing a ROM doesn't work, it looks like it's flashing, but nothing happens.
- MiPCSuite doesn't recognize the phone.
- Using adb.exe and fastboot.exe I can see the phone, when I use adb devices or fastboot devices.
- Using fastboot.exe getvar all, gives me a lot of variables, so my laptop can connect to my phone using fastboot
- Settings, Mi Account, Devices shows my phone, with the changed device name
- When using the Mi unlock tool, the account number there is the same as the one on the phone. But when the tool sees my phone, it displays a different device name. It says Mi Phone. That might the culprit.
So, still no go in flashing or unlocking the bootloader.