One page not secure

I have a site that has an embedded block linking to a secure chatroom, this chatroom should allow video calls.

The page on which the chat room is embedded when published shows the page is unsecure ie http:// rather than https://

The video function only works on a secure site - why does the squarespace page change to unsecure? All the other pages are as expected secure?

Many thanks for any advice.

<div style="width: 100%; height: 800px;"><div id="rt-c8c5f774ed537e39431cbd06a7ed3a10"></div> <script src="https://rumbletalk.com/client/?9V7K16:3"></script></div>

Can you share link to page in your question? We can check easier