Problems running rpiboot on HA Yellow C5

Hi I’m new here and just got my first HA yellow C5; trying to run rpiboot nothing happens at the HA. I followed the official instructions.
It runs the installer on the PC, but after finsih the red Led on the HA board stays red.
In the next step the RPi installer does not find storage.
Someone has any suggestion.

Did you put a Compute module in your yellow ?

Yes, the RPi CM5

What version? The lite doesn’t have storage.

Rpi Module 5 - 4GBRAM, 32GB eMMC

I got this now