hi, u have by a xperia 10 x and followed the instruction for installations;
i have try to reinstall old android version like wrote :
Your phone should run Android 9, do not update to Android 10 in case it is offered.
through Emma tool(https://jolla.zendesk.com/hc/en-us/articles/115004283713) on Windows.
emma tool failed to install android 9
so in this moment i have a mobile in loop that try to boot android, don’t reinstalling factory option,
and i don’t know like put it in off for try to reinstall another android with Emma tool.
someone have tips for me?