bookmark on page not working

I can’t get a bookmark link/anchor to work on my classic editor Word Press. I’ve used book marks before successfully on another page. I can’t understand why it’s not working.

I’ve password protected the page because it’s half finished. Use this password:

Here is the anchor: <h5 id=”C4″>Study</h5>
Here is the bookmark:<a href=”#C4″>Jump to Study

Thanks for your help.

The page I need help with: [log in to see the link]