U4919DW, how to connect PS4 Pro 4K?

Good evening,

I have a Dell U4919DW monitor and am trying to connect a PS4 Pro 4K to HDMI. I've tried two different cables but no resolution greater than 1080p and no option for larger. So I am wondering if the screen features that it even has the ability to connect 5K to HDMI why only connects to 1080p?