Hi Ilmisu. I had the same issue with the 3H. I managed to get the token doing the following.

1/ Remove the Smarthome directory from your internal file system on you mobile (or rename it to be safe)

2/ Install latest version and register your device until the end. For 3H use a European location as it won’t show up if you register it against the Chinese Xiaomi service. I used Germany. You should be able to acces your Air purifier and control it properly.

3/ Check it but you still won’t have any Smarthome directory as the latest version of the Xiaomi Home does not use it anymore.

4/ Uninstall Xiaomi Home completely from your device using Google Play

5/ Install manually the APK for version 5.4.54 (you can google to find it)

6/ Launch it on your device and log in against European Service with the same login you used previously (no “Germany” in this version). You should now see the same list of devices showing up in Xiaomi Home. Don’t try to access the Air Purifier as it will not work, the plugin is not working with this version of Xiaomi Home. Just make sure you see the Air Purifier listed that’s all.

7/ Close Xiaomi Home completly

8/ Check you local storage on your device. You should now find a file there SmartHome/log/plug_DeviceManager/year-month-date.tx file Make sure you use the file in this location. There is another one in the directory above with the same name but it is useless.
Inside this file you should have the list of all registered devices in Xiaomi Home with their respective tokens.

9/ You can then upgrade your Xiaomi Home app from Google play and use it to control your Air Purifier.

Please be aware that I am still not able to control the Air Purifier from within Home Assistant as I get a 5001 error code, but this seems related to the xiaomi-miio component and underlying python-miio latest corrections not beeing merged yet into the 107.7 version of Home Assistant. But it should be working soon. I have tried accessing it from my workstation using the token I got with the above procedure and mirobo pyhton script and I manage to communicate with it.

As a reminder keep in mind that every time you reinitialize your device WiFi, a new token is generated and you have to do all this procedure again from start… So keep the 5.4.54 APK on your device as you may need it again to get a token.