unpacking the sent packfile failed on the remote

Getting error while pushing a new branch using library

unpacking the sent packfile failed on the remote; class=Net (12)

but if I go to directory and try to push the branch using Git with command, it works without any issues.

git push <remote> refs/remotes/<remote>/<branch>:refs/heads/<branch>

So I am not able to figure out if I am doing anything wrong in script that I wrote or if there is some issue on server.

Here is sample script

    let ssh_key =
        std::path::PathBuf::from(<SSH private key path>)
    let repo = git2::Repository::open(".")?;
    let mut remote = repo.find_remote(<remote_name>)?;

    let mut push_options = git2::PushOptions::new();
    let mut cbs = git2::RemoteCallbacks::new();
    cbs.credentials(|_url, username, _allowed_type| {
        git2::Cred::ssh_key(username.unwrap(), None, &ssh_key, None)
    });
    push_options.remote_callbacks(cbs);

    remote.push(
        &[&format!(
            "refs/remotes/upstream/<branch>:refs/heads/<branch>",
        )],
        Some(&mut push_options),
    )?;

Start with the sample remote.push call and compare its refspec, remote selection, and SSH callback with the working Git command. Reproduce the push and inspect the complete library and server output; done means identifying whether the failure is in the Rust call or the remote server and documenting a confirmed cause.