File not found during System upgrade to Leap 15.5

Trying to upgrade from leap15.4.1 to leap15.5.1 using the command zypper --releasever=15.5 dup --download-in-advance but i’ve got the error message :

Retrieving: libxxhash0-0.8.2-lp155.22.1.x86_64 (Software for Scientists and Engineers (15.5)) (6
Retrieving: libxxhash0-0.8.2-lp155.22.1.x86_64.rpm …[not found]
File ‘./x86_64/libxxhash0-0.8.2-lp155.22.1.x86_64.rpm’ not found on medium ‘https://download.opensuse.org/repositories/science/15.5/
Abort, retry, ignore? [a/r/i/…? shows all options] (a):

When i’ve searched for the missing file following the previous link, i found another file libxxhash0-0.8.2-lp155.23.1.x86_64.rpm different.

How to correct this ?

Did you disable all not standard repos before you started the upgrade?

How is it?
i followed the officila guide SDB: SYStem upgrade and there is no disabling repos.

There is:

Extra repositories handling

https://en.opensuse.org/SDB:System_upgrade_to_Leap_15.5#Extra_repositories_handling

Also you have been running in an Update of the science Repo
File ‘./x86_64/libxxhash0-0.8.2-lp155.22.1.x86_64.rpm’ not found on medium
vs
libxxhash0-0.8.2-lp155.23.1

Apart from what @Sauerland already pointed out, I would never want to have any non-standard repos active during such a huge action. It will be already fine when more then 1500 packages are installed without problem. Then after I would enable the extra repos I have one by one and install from them what I need (and for Packman I would do the vendor switch).

Juts my personal approach.

I also do only upgrade with enabled Packman, all other Repos will be enabled and switch packages (by hand) after reboot of the new openSUSE Release.

Nothing disabled?

I think that means all disabled…
Otherwise I could not enable, because they are…

Try enabling all repos and doing this:

As can be seen at the initial terminal output, this is not the problem.
Instead of recommending some random stuff, it is always adviced to follow official upgrade procedures as pointed out by Sauerland in his comment.

Additionally , the problem that can be seen in the first post is, that either auto refresh for this repo is disabled or the mirror was in a syncing state…

The TO may show
zypper lr -d