error on update

[acedigitalpro]

how to resolve?

[XNinety9]

That screen comes from a pre-4 Omarchy (a git checkout of basecamp/omarchy tracking master). The repo is now omacom/omarchy and its default branch is quattro: there's no master branch anymore (git ls-remote https://github.com/omacom/omarchy refs/heads/master returns nothing), so the old git-based update has nothing to pull.

The way forward is the upgrade to Omarchy 4, which is now installed as pacman packages. The upgrade script is self-contained and meant to be run directly on older installs:

curl -fsSL https://raw.githubusercontent.com/omacom/omarchy/quattro/bin/omarchy-upgrade-to-quattro -o /tmp/upgrade-to-quattro
less /tmp/upgrade-to-quattro     # read it first
bash /tmp/upgrade-to-quattro

It's a one-way upgrade (you can't go back to 3.x), and the 4.0 release notes advise taking a backup of important data first. After that, updates go through omarchy update / Update > Omarchy as usual.