Integrate diyHue and Conbee 2

Hello everybody,
I’m really new to diyHue and Conbee.
I read that they both work together but currently not for me.

I had a Raspberry Pi 4B and I installed the diyHue as a docker container that is on IP Address from where I can reach the diyHue website.
Then I plug in a conbee 2 usb stick and followed the instructions on the conbee website.
The installation process finished without errors and the phoscon website is available on Port 8080!
On my mobil device I installed HUE Essentials where both (diyHue and Phoscon) will be listed as bridges. But I only can add one at a time!
I paired 2 lamps via the phoscon website and when I connect the HUE Essentials to the Phoscon Bridge I can controll them.
That means, in general the zigbee works.

But how can I add the conbee (or phoscon) with diyHue. I searched this group but the articles found are to technical for me.
Can someone assist me in bringing the both together so I can controll the lamps over diyHue?

Thanks in advanced

Did you follow these instructions: