Embedding Google Calender

I want to embed a google calender into my wordpress.com blog. I understand that the way to do it is via the method shown in
https://en.support.wordpress.com/google-calendar/
but when paste the code
<iframe src=”https://calendar.google.com/calendar/embed?height=600&wkst=1&bgcolor=#FFFFFF&[email protected]&color=#182C57&ctz=America/Denver”/calendar/embed?height=600&wkst=1&bgcolor=#FFFFFF&[email protected]&color=#182C57&ctz=America/Denver&#8221; style=”border-width:0″ width=”800″ height=”600″ frameborder=”0″ scrolling=”no”></iframe>
into the text panel, the embed code doesn’t appear, it just strips out the iframe tags and leaves a link.
https://calendar.google.com/calendar/embed?height=600&wkst=1&bgcolor=#FFFFFF&[email protected]

Does anyone else have the same problem? If they can get it to work, can someone tell me the right way to go about this? Having a wordpress.com blog means I can’t use a plugin.

Thanks