Different coding on youtube

Where did you get that code?

You should have something like this:

<iframe width="560" height="315" src="https://www.youtube.com/embed/4qsGTXLnmKs" frameborder="0" allowfullscreen></iframe>

And replace it with shortcode like this:

iframe src="https://www.youtube.com/embed/4qsGTXLnmKs"]

Which code?

I saw the code on the plugin site look at my screenshot: Screenshot

It’s the [iframe] code that not working.

Which code?

This is not the proper youtube link for embed video:

src="https://www.youtube-nocookie.com/embed/W7mNmiW9qts?rel=0"

Should be this one: src="https://www.youtube.com/embed/W7mNmiW9qts"

Does this shortcode work for you?

[iframe src="https://www.youtube.com/embed/W7mNmiW9qts"]

That’s not the code I show in the post or don’t you see the whole code? It was:
<iframe width=”560″ height=”315″src=”https://www.youtube-nocookie.com/embed/W7mNmiW9qts?rel=0″frameborder=”0″allowfullscreen></iframe&gt;

I see your code very well.
And your code is just html iframe tag.
It will work without the plugin but can be stripped by WordPress sometime.
And also your iframe has not proper youtube source url address. Its youtube-nocookie.com and should be youtube.com.

And the code I posted above with square brackets is the shortcode which will be executed by iframe plugin.

Does this makes more sense now?