Your repos section is a bit messy .. but more importantly it is out of order .. it should look more like;
[cachyos-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos-core-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos-extra-v3]
Include = /etc/pacman.d/cachyos-v3-mirrorlist
[cachyos]
Include = /etc/pacman.d/cachyos-mirrorlist
#[core-testing]
#Include = /etc/pacman.d/mirrorlist
[core]
Include = /etc/pacman.d/mirrorlist
#[extra-testing]
#Include = /etc/pacman.d/mirrorlist
[extra]
Include = /etc/pacman.d/mirrorlist
# If you want to run 32 bit applications on your x86_64 system,
# enable the multilib repositories as required here.
#[multilib-testing]
#Include = /etc/pacman.d/mirrorlist
[multilib]
Include = /etc/pacman.d/mirrorlist
# An example of a custom package repository. See the pacman manpage for
# tips on creating your own repositories.
#[custom]
#SigLevel = Optional TrustAll
#Server = file:///home/custompkgs
That is you have cachyos-extra above cachyos-core and it should be reversed.
It is not the cause of the ‘error’ here but it should still be rectified.
Unless it persists for a long period it is a non-issue of the packages being rebuilt and/or mirrors syncing.
Just wait a bit.