First two LEDs flickering

Hi Hyperion Team,

I followed your guide with the following configuration:
Raspberry Pi 3b+
2,5m LED Strip https://www.aliexpress.com/ite…042311.0.0.49fe4c4d1Pcvhf
Mean Well RS 50-5 https://www.meanwell-web.com/e…r-supply-output-rs--50--5

The LED strip is cut into 5 pieces and connected with clips. All in all 84 LEDs.
The RPI is running on the newest LibreElec and with the Hyperion configuration from the guid.

When I start hyperion with the HyperCon the first two LEDs are flickering. The other LEDs don't show anything.
After some time of flickering the second LEDs stays on one color.

What am I missing?
Thanks a lot for your help!

I am very new to this and have no idea. I'll try to rewire it and test it with some other part of the LED stripe.

Edit: I replaced the first part of the LED strip and it worked. When I start Hyperyion service and I am able to see the rainbows swirl and I can change the LED colors.

I connected an external grabber (Basetech BT116) and have been able to grab a screenshot from the grabber in the Hypercon programm.
The LEDs stay dark though.....

Edit2: I am too stupid to use the Hypercon app. Got it all working