Никита

$url = 'https://example.com/files/file-название файла (1).docx';
$url = preg_replace_callback(
    '/[а-яА-Я\s]+/ui',
    static function ($matches) {
        return rawurlencode($matches[0]);
    },
    $url
);

// https://example.com/files/file-%D0%BD%D0%B0%D0%B7%D0%B2%D0%B0%D0%BD%D0%B8%D0%B5%20%D1%84%D0%B0%D0%B9%D0%BB%D0%B0%20(1).docx

$hasReasonOne = (array_search('NUMBER 1', array_column($array["info"]["Reasons"], 'reason')) !== false);
foreach ($array["info"]["Reasons"] as $key) {
    if ($key["reason"] == 'NUMBER 1') {
        ...
    } elseif (!$hasReasonOne) {
        // if reason one not exist
    }
}