Device is not accessible after formatting the microSD

Hi, 

this state is healthy, I have no explanation for that.. 

You can try to connect X1P1 to a dhcp router as well as your PC. Then you need to check the IOTs IP address in the router's webserver and connect via this interface.

Another thing you can do is to use a UART cable (e.g this one) to establish a serial connection and check what is going on. 

But honestly I think there is something going wrong with your IP addresses, if you can't even ping it in its default state. 
Or we have a situation I have never faced before.

Best regards!