Git: Repository not found after authenticating, checking origin and upstream

Question

I am trying to push to git from the Windows GitHub CLI but keep getting ERROR: Repository not found. I have successfully pushed to this repository before. My PC is also connected to a different remote under the same github account that I pushed to the other day with the same ssh key.

Things I have tried:

• Re-authenticating with gh auth login
• Ensuring that the account I am authenticating with is the one that has access to the repository I am trying to push to
• Deleting my credentials from the credential manager in Windows, then re-authenticating
• Checking my upstream with git branch -vv and git name-rev @{u} (everything looks good)

This is my config file:

[core]
        repositoryformatversion = 0
        filemode = false
        bare = false
        logallrefupdates = true
        symlinks = false
        ignorecase = true
[user]
        name = account_with_access
        email = email_for@account_with_access.com
[pull]
        rebase = true
[remote "origin"]
        url = git@github.com:someone_else/repository_I_have_access_to.git
        fetch = +refs/heads/*:refs/remotes/origin/*
[branch "main"]
        remote = origin
        merge = refs/heads/my_files # note: not main
[push]
        default = upstream

Someone else is using main in the remote, so I generated another branch which I push to exclusively (my_files). Could some of the config around this be part of the problem? Or could it have to do with having another remote on the same machine under the same account? I am not well-versed in github best practices, so I realize I may be missing something very obvious to better-trained git users.