N: Unable to locate package when adding another repository

So I am trying to setup something called ombi. Ive added the repo to source.list and did update. I also see the repository show up in the update logs. But when I try to install ombi I get N: Unable to locate package ombi. I also have the key in apt-key list.

The most common reason for this would be that there are no suitable arm64 binaries in the repo.