XPS 15 9500, U2723QE stuck at refresh rate 30Hz

Adding a bit more clarity.  I was using the same HDMI cable, same Dell adapter and same port on the XPS both before and after the 60hz option dropped and only one day between the before and after. 

To receive assistance from Dell support agents, they need to first verify the ownership and warranty status. Click the blue "Get Help Now" on the right to start a private live chat session. Share the private U2723QE and XPS 15 9500 Service Tags with them.

Why use Dell adapter + HDMI when you can connect via the straight U2723QE 1 M USB-C to USB-C cable?

Simplify the connection setup and retest =

AC power connected to XPS 15 9500 left side #1 Thunderbolt 3/USB-C port
XPS 15 9500 left side #2 Thunderbolt 3/USB-C port --> U2723QE 1 M USB-C to USB-C cable --> U2723QE #5 USB-C Video + Data port

Thank you, Chris.  I’ll give that a try.  Numerous calls to premium support.  All pointed me to use  shared usb-c-dp shared port on right side of laptop for video signal regardless of cable type.

I will say 60 hz was there and used at first setup with the cabling I noted.  Only changes were software and settings performed by premium support.

Hi Chris.  Same result after testing per your suggested method.

Have you entered the U2723QE Menu OSD- Others and ran Factory Reset?

Then go to U2723QE Menu OSD- Display- USB-C Prioritization and set it to High Resolution. Exit the Menu saving changes. Does 3840x2160 60Hz appear in the Windows Display settings?

After resting the monitor, nvidia control center settings back to factory defaults and flipping the USB-C monitor setting back to high resolution , 3840x2160 @ 60 is now available.  I believe the prioritization toggle was greyed out prior to reset due to various changes made by premium support in response to my inquiry around to improve saturation, text clarity, temp, etc.  Are you able to assist with confirming where a few miscellaneous settings should be for the best monitor output once the WD22TB4 dock is installed?  To set up for the below additional questions, sharing that my system was factory default in terms of NVidia Control Center settings as I don't really play games, do rendering, or photo work.  However, tech support changed a lot in Nvidia Center and Display Manager in trying to get best monitory color saturation and clarity.

After the resets, Windows display settings Color Profile drop down is now greyed out.  Is that they way it should be or should there be a few to choose from where sRBG is the preferred choice?

In Windows Display settings, should Use HDR be off?

In Dell Display Manger, under Color tab, should that be set to Manual (if so, Standard or sRGB?)

In Dell Display Manager, under Display, Should Smart HDR be set to Off?

What are the fields I need to change in order revert back to factory in Nvidia Control?  Currently set as:

PhysX Config: Auto (both green boxes pointing to Intel tile)

Manage 3D: Global Tab: Auto Select

3D Program Tab: (1) Acrobat (2) Use Global Setting (Autoselct: Nvidia)

Adjust 3d Settings: let the 3d app decide

Correct that best cabling from WD22TD to monitor for XPS15 9500 FHD with graphics assist card is male to male DP 1.4 cable that came with the monitor?

In order to make use of built-in monitor KVM, does that same dock to monitor DP cable also handle this linkage while preserving 60hz and usb-3 speeds or do I also need a USBA to USB-C to handle that?

Thanks in advance for the help here.

Looking for confirmation of whether the below two 4k monitor configuration will work where both monitors are at 60 hz and, if so, how to run all cables to achieve best display quality.  Also, any software settings needed to a certain way in on-board monitor menu, Dell Display Manager and Windows Display settings to accomplish all of this.

XPS 15 9500 1650ti assist TB3 HBR2

Charging XPS15 9500 at 130 watts via TB dock

Dual 4k monitors – both U2723QE

Both monitors running 3840x2160 AT 60hz

Dell dock WD22TB

Cherry RF-only keyboard

4k webcam at 30fps (not purchased yet)

Use XPS 15 9500 or work laptop Latitude 5420 via WD22TB4 thunderbolt connection one at a time and sharing Cherry keyboard and webcam via built-in U2723QE KVM.