iPhone X stopped working after installing new software

Thank you for your response and your help. I contacted apple support for help as you told me . The agent asked me to follow the exact

steps you provided and I told him I did that using different devices and it still didn’t restore my phone. He told me that there is nothing they could do beside me mailing my phone to them. I agree to that and he told me my warranty had already expired since I had the phone for almost 2 years now ; and so it will cost me $575 to get a new one mailed to me while they take this one. I told him he is asking me to buy a new phone without answering my question as to why my phone is no longer working. His reply was that on the market a new iPhone X will cost me much more, so am getting a discount. This very upsetting because my phone had no issue, no crack and worked perfectly until two days ago the software updated automatically. Now I can only rely on apple Technicians online because all stores are closed, and third parties don’t have open appointment according to the agent .

I spent all day doing that , it still didn’t work .