Some users reported that some packages are not being updated on the Server during the update to Uyuni 2021.09.
The cause and the workaround is now documented at: https://github.com/uyuni-project/uyuni/issues/4244
The problem is in fact that openSUSE is shipping some SUSE Manager packages, so we filled https://bugzilla.opensuse.org/show_bug.cgi?id=1190851
This announce is now posted at the website, and Twitter, and it will be part of the Release Notes for Uyuni 2021.10 if the problem is still not solved.
Sorry about the inconvenience.