Looks like you may have solved the issue.

here's how we do it.
When you click inside any one of the blocks, a toolbar appears. On the left corner of the toolbar, you'll see the paragraph symbol. It looks like a backwards capital P with a double side. Click that to reveal a comprehensive menu, and choose HEADING..

Hope you get it sorted out...looks like some suggestions below.

Check the screenshot:

These should help, otherwise, let me know,

In the first step you can choose either:

- Heading
or
- Headline

Mike

I was just going to suggest the same thing, but Phil has you covered, Julia!

Have an excellent day!

Jeff

if you click on the block you want to change and then click on the left hand icon in the menu that pops up you can change easily from a paragraph to a heading and other blocks....