Maui Tom

I have recently purchased a 2022 GMC Sierra AT4 2500HD. The dash has the lens for a head up display. I cannot figure how to turn it on or infact it even has a HUD. Why would GMC make a dashboard with HUD lens and no way to activate it. I have looked in the info settings etc. I do not have a HUD button as indicated in most videos. Again, why have the lens in the dash? Cheaper just to put that in than to make one without it?? Anyone have any thoughts?