NoSuchElement exception inside an iFrame while trying to findElement

Question

I'm trying to find an element inside an iFrame, here's my code:

WebElement frame = driver.findElement(By.xpath("//*[@id='homepage-generator']/iframe"));
        driver.switchTo().frame(frame);
        frame.findElement(By.xpath("//*[@id='pqkztovxrnzublksfhauksotowyaetpeidbnyyekxzlhidnpd-max-span']/input"));

Can you people help please? Thanks.