private-composer-installer: Class 'FFraenz\PrivateComposerInstaller\Environment\LoaderFactory' not found

For some reason i’m getting this error when deploying my site after I ran composer update.

PHP
Fatal error: Uncaught Error: Class
'FFraenz\PrivateComposerInstaller\Environment\LoaderFactory' not found in
/www/{site_name}/public/releases/129232182/vendor/ffraenz/private-
composer-installer/src/PrivateComposerInstaller/Plugin.php:102

The error happens at this stage in the deployment Installing advanced-custom-fields/advanced-custom-fields-pro (5.9.1). It’s been working fine for months now, so I’m not sure what’s going on. Everything works on my local also.

Here’s my ACF declaration in my composer.json file.

{
      "type": "package",
      "package": {
        "name": "advanced-custom-fields/advanced-custom-fields-pro",
        "version": "5.9.1",
        "type": "wordpress-muplugin",
        "dist": {
          "type": "zip",
          "url": "https://connect.advancedcustomfields.com/index.php?a=download&p=pro&k={%ACF_PRO_KEY}&t=5.9.1"
        },
        "require": {
          "ffraenz/private-composer-installer": "^5.0",
          "composer/installers": "^1.4"
        }
      }
    },

Has anyone had this issue before?

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