Activation Lock Problem
Hi. My father passed away 2 months ago. He had an iPhone X. I wanted to reset his phone and use it myself, but it has activation lock. I need to remove the Apple ID and password from the phone but I don't know his id and password. So what should I do about this issue? And also, I don't have the phone's receipt, where should I get the receipt from? Please help me. Thank you.
iPhone X