The USB 3.2 port on that system has a 10 G bandwidth.  Two 2K monitors are going to be close to or over that limit if connected to the dock, and then to that port. Is that how you are trying to connect these?  If so, that's why you can't get both monitors to 2K resolution.  
Hello, I have the laptop Dell Latitude 5511 with Intel i7-10850H CPU and Intel UHD 630 GPU, two monitors Dell U2715H and a dock Dell WD19S. When I connect monitors to the dock and then dock to the laptop, one monitor works with 1080P resolution and one with 1440p. Also, I tried to use the HP G5 dock station but without a result. What I should do to use both monitors in 1440p resolution?
Help me to setup 2k resolution on two monitors Dell U2715H and Dell Latitude 
5511