Composer\Downloader\TransportException: The "drupal.org/packages.json" file could not be downloaded (HTTP/1.1 404 Not Found)

In Drupal 8.9.x, After composer cache-clear. I am getting this error [Composer\Downloader\TransportException] The "drupal.org/packages.json" file could not be downloaded (HTTP/1.1 404 Not Found) .

I can't run the composer install or composer update.

I tried to remove the vendor folder & composer.lock files too.

Even i tried,

• composer config -g repo.packages composer https://packages.drupal.org

• tried composer diagnose and after that composer update -vvv

• composer config -g repositories.drupal composer https://packages.drupal.org/8

• composer config -g repositories.drupal composer https://www.drupal.org/packages.json

• composer config -g repo.packagist composer https://packagist.org

But no luck.

is something wrong? before the composer cache clear it was working fine. it happens only on after composer cache clear. Any help appreciated.

    "repositories": [
            {
                "type": "composer",
                "url": "https://packages.drupal.org/8"
            },
            .....

The drupal package repository is https://packages.drupal.org/8, none other. it should appear, in most cases, alone as the only added repo in composer.json:

    "repositories": [
        {
            "type": "composer",
            "url": "https://packages.drupal.org/8"
        }

But as you have done it, with a named key, it will be as follows, which should be fine:

    "repositories": {
        "drupal": {
            "type": "composer",
            "url": "https://packages.drupal.org/8"
        },

I think the problem you are experiencing is that by passing the -g flag to composer, you are setting the value globally (for all projects) but the project's own composer.json may have a differing, or a wrong, configuration.

I ran this composer config command, then it works.

"composer config -g repo.packages composer https://packages.drupal.org/8"