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USB-C problem with full frequency and resolution on extrenal display

On HP Elitebook 830G5 laptop I have Intel UHD Graphics 620 and try to connect LG 4K display (with USB-C, Display port and HDMI connectors). Display and laptop according to manual should support 3840x2160/60Hz through USB-C which was checked on Windows10 system and is working perfectly. On Linux (any distribution) when I'm connecting my LG 4K monitor to Display Port. It is assigning to DP-2-2 socket and I have full 3840x2160 with 60.00Hz But, when I'm connecting the same monitor through USB-C port, then it is connecting to the DP-1 socket and the maximum that it can achieve is 3840x2160 with only 30.00Hz. But I'm making some trick: I'm connecting the same monitor through HDMI, so it is connecting to DP-1 socket, and simultaneously I'm connecting USB-C, and disconnect HDMI cable, and now USB-C is connecting to DP-2-2 socket (because DP-1 was probably occupied by HDMI) and I can have full 4K with 60Hz. As I mentioned, on Windows there is no issue.

Steps to reproduce problem:

Step 1: Connect extrenal display through USB-C port and setup 3840x2160 mode with 60.00Hz. Result: Extrenal display is going blank. This mode is not working.

Setp 2: Connect extrenal display through USB-C port and setup 3840x2160 with 30.00Hz Result: Extrenal display is connected to DP-1 and is working in this mode.

Step 3: Connect extrenal display through DisplayPort and setup 3840x2160 with 60.00Hz. Result: Extrenal display is connected to DP-2-2 and is working in this mode.

Steps to forcing UCB-C to working in 3840x2160 with 60.00Hz mode:

Step 1. Connect extrenal display to HDMI port Result: Extrenal display is connected to DP-1 and is choosing 3840x2160 with 30.00Hz

Step 2. Connect simultanseosly the same display through USB-C and then after few seconds disconnect HDMI cable Result: Extrenal display is connected to DP-2-2 and is working in 3840x2160 with 60.00Hz This is working till restart or hibernate system or when display is turn off/on by screensaver

Here is dmesg: dmesg-USBC

Here is xrand when connecting through USB-C xrandr-USBC

Here is xrand when connecting through DP xrandr-DisplayPort

Here is xrand when connecting through HDMI and then USB-C (trick) dmesg-USBC-after-HDMI

My system:

arch: x86_64

kernel: 5.4.0-52-generic

distribution: Ubuntu 20.04.1 LTS

dmidecode: dmidecode

Display connector: USB-C

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