KVM and lenovo thinkpad

Can't get my lenovo company own thinkpad T440 with a mini display port to operate with Dell KVM on U3223QE monitor I can see my desktop and laptop , but when I switch to laptop using mini dp to display port or mini dp to usb-c or mini dp to hdmi it always state display port, usb-c or hdmi not found. Does anyone have a solution to this besides the company giving me a new laptop