HP Universal USB-C Multiport Hub compability with external monitors

[Simsec]

I have purchased some items which i cannot use to the fullest. I bought a HP Spectre X360 (intel 13th gen) together with a HP Universal USB-C Multiport Hub to use for all types of connection. 

My HP Spectre have two Thunderbolts 4 ports and one of them is connected to the USB hub. My problem is that my external monitors cant be used to its fullest refresh rate. I have a AOC 24G2W1G8 (240HZ) and AOC 24G2W1G4 (144HZ) 

I connect the AOC 24G2W1G8 (240HZ) to the USB hub display port, and the AOC 24G2W1G4 (144HZ) to the HDMI port, that restricts each monitor to a maximum 100hz each. I can use one screen with 120hz but then the secondary only can be viewed in 60hz. I can get 240hz if i connect it to the display port alone, but then for some reason it switches to 6 bit in color depth which makes it looks bad. If i choose 144hz the monitor goes black with no signal.

The only combination that works is to connect AOC 24G2W1G8 (240HZ) to the computers second display port (with a USB-C adapter) And the AOC 24G2W1G4 (144HZ) to the USB hub display port. That makes all the HZ usable. But even that was tricky, it all depends on what monitor is connected first.

I have tried to switch displayport and HDMI cabels back and forth, also tried with an Elitebook 640 G9 but with the same result.

This is really annoying  this hub seems fragile and according to the specs no limitations in refresh rates were listed. Since it use USB-C/Thunderbolt it should be able to deliver accordingly.