Autoinstallable Distribution SLES 15

Hello, I have a SUMA installed in the lab and am trying a few things out.
I’m stuck with the autoinstallable distribution of SLES15.
Rocky 8, 9 and RH8, 9 work perfectly.

I have a synchronous base channel: SLE-Product-SLES15-SP5-Pool for x86_64

I used tftpboot-installation - version SLES 15.4 is the SUMA version. Afterwards I installed the tftpboot installation of SLES 15.5

Now I have two directories
/usr/share/tftpboot-installation/SLE-15-SP4-x86_64
/usr/share/tftpboot-installation/SLE-15-SP5-x86_64

At next step, I have created a profile for SLES15.5. (i dont use SLES15.4)

When trying to install PXE it gets stuck: Installation medium is not available!

When configuring the Autoinstallable Distribution, I specified /usr/share/tftpboot-installation/SLE-15-SP5-x86_64 as the tree path

For the variables I have media_path=/ks/dist/org/1/SLE-15-SP5-x86_64

As Autoyast profile I use SUSE / manager-build-profiles from github: sles15-sp5-autoyast.xml

I know that with a PXE installation of SLES the files should be located under /srv/tftpboot/*. If this directory already exists then the tree will be copied to /usr/share/tftpboot-installation.

I copied the directories from /usr/share… to /srv/tftpboot - no success.

I noticed that an empty directory was also created: /srv/tftpboot/suse-tftp-install.

In which directory do the SLES files belong and what is the correct URL variable for the installation?