Face ID on iPhone 11 Pro Max has stopped working

A couple of days ago the Face ID on my iPhone 11 Pro Max stopped working. I googled it and followed an online guide for trouble shooting the problem. My software is all up to date and my phone is sparkling clean. There is nothing covering the camera.

A friend suggested resetting the Face ID so I did so but despite moving the phone, changing the lighting and adjusting the distance the camera doesn’t pick up that I even have a face let alone let me reset Face ID.