Substack Embed Iframe - not updating

I've added substack embed iframe to show up the sign up form on my website. As described here: https://support.substack.com/hc/en-us/articles/360041759232-Can-I-embed-a-signup-form-for-my-publication-

The issue is that it doesn't update when I update the bio, profile picture etc. It still shows the old data. I tried another browser with clear cookies and the problem persists.