Troubles with Lenovo Thunderbolt 3 Dock Gen 2

Hi, I’ve got Framework 13 DIY (AMD Ryzen 7840U) and a lot of issues with docking station which is Thinkpad Thunderbolt 3 Dock Gen 2. Docking station itself works fine with another laptop (Thinkpad), but with Framework it works… sometimes. At first I’ve thought it might be OS issue (I use Arch BTW), but it’s probably not this, as I can notice problems even before powering on.
Namely I connect thunderbolt cable and sometimes I can see laptop is charging (red led) or is fully charged (white led), sometimes - just no leds. Or red led blinking slowly. It’s hard to determine why sometimes it works, sometimes not at all.
Changing USB-C port sometimes helps, sometimes not.
When it works, it works fine. Unless I try to change something - e.g. when I disconnect thunderbolt cable and connect it again, it will not work most probably.
BIOS is up to date (3.03)

How can I solve it? I can buy another docking station if it will work - can you recommend any?
Have a lot of external devices (Jabra, camera, 2 monitors, keyboard etc.) so I can’t survive with 4 ports only.