Hi there and welcome
Can you please hold the volume DOWN and power buttons for 10 seconds, the release.
Then power it on and tell me if it now works please.
Do you hear any sounds coming from the phone at all?
Can you hold the power button for 60 seconds then release.
Then press volume up and power for 6 seconds till you see something appear on the screen.
Does anything show up?
It is the internal mainbooard that has faulted, this now confirms it
I am really sorry about this and you are going to have to return the phone to have it replaced. It will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you.
I am really sorry about this, and if you have problems, or would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the page, then submit, that would be greatly appreciated.