Item was missing from the box

I ordered a iPhone 17 Pro Max from xfinity. However, when fedex delivered it there was no iPhone in the box. Although the person that took was so kind to leave a box cutter inside after they taped it back up. I have been waiting on a email so I can upload the documents required. I just received an email saying that I will be billed for a line that I still dont have the phone for. I dont believe that would be right seeing that this has been a issue for customers ordering from xfinity who uses a company like fedex.