Error installing Debian 12 (bookworm)

Hello. When trying to install Debian 12 on a remote host, an error occurs during the installation process:
E: Package ‘python’ has no installation candidate.

I created a new operating system and added installation media according to the required instructions.
The process of loading the PHEboot image goes without problems or errors and the OS installation begins. But when the process comes to installing packages I get this error.

I tried to install Debian 12 in both legacy mode and UEFI mode, but I see the same errors.

I checked all the preparation templates but I still couldn’t find where the installation of the old Python package comes from.

Have you encountered a similar problem and what are the ways to solve it?

Foreman and Proxy versions:

I use foreman Version 3.1.1 and foreman-proxy Version 3.1.1.

Other relevant data:
Unfortunately, I can’t attach screenshots of errors because my account was created recently.