The error that wilirius posted said it is timing out, also that WooCommerce works fine using the same function.
ACF does not set a value for timeout so it will use the defualt.
The default value for timeout use by WP is 5
The timeout used by WooCommerce for wp_remote_get() is 60
$response = wp_remote_get( $this->get_language_package_uri(), array( 'sslverify' => false, 'timeout' => 60 ) );
So, that’s is a difference.
Try adding a timeout arg to the call in ACF of 60?
