There's no hard reset in the phone itself. What you can do is to perform a software repair using Xperia Companion which will reset the phone and the lock screen password. But if the phone is in lock down mode with Google Device Protection, you can't reset the lock by yourself. The phone needs to be sent to a service location in case you don't have access to the Google account used for lockdown. But if you don't have a receipt for the phone i recommend that you contact the person who gave you this phone. The service location will need proof of purchase to remove the lockdown.
Actually I work as a sales rep for a telecom operator in Sweden and I am the Sony ambassadeur in my store. I recived the phone directly from Sony in Sweden before it was released. Sony have not had the time to help me with this issue so I figured I could try the Support forum.
So my question still remain, how do I hard reset the Xperia X?
There's no hard reset in the phone itself. What you can do is to perform a software repair using Xperia Companion which will reset the phone and the lock screen password. But if the phone is in lock down mode with Google Device Protection, you can't reset the lock by yourself. The phone needs to be sent to a service location in case you don't have access to the Google account used for lockdown. But if you don't have a receipt for the phone i recommend that you contact the person who gave you this phone. The service location will need proof of purchase to remove the lockdown.
