RSS Not Working

Hi All

I hope someone can help me. I have recently launched my site, https://www.cashalerts.co.uk and never used RSS before. In my theme, I have inserted the rss url to the correct field – https://feeds.feedburner.com/cashalerts?format=xml

As you can see, I’m using feedburner. When I go to my live site and click on RSS, it only displays one of my posts (in its entirety). None of the other posts are included. I have not done anything special to that post. The only unique aspect to it is it was the first post I published.

Can anyone offer some guidance as to why the posts are not automatically not added to the rss feed. Also, how do I get it to just show the headline or manual excerpts?

Thank you very much for reading!

Best regards

Jon