Gutenberg Block Editor and Preview different

Hi there!

I’m building a website for my blog. For the blog archive page, I used the Gutenberg block editor, as I don’t like the default template that Astra (my theme) uses. When I view my site in the block editor, everything looks as I want it to. When I click on “preview” however, all headings are suddenly displayed using a different font and in italics. Also, each time that I visit the site, my page title in the top left corner is also displayed in the wrong font and italics. There, the error goes away after loading another page and then returning back to the home page. I already checked the settings of the theme under “customize” and set it to the same font I used in the block editor. I imported the template for my site from Astra’s starter templates and use a custom font for some of the headings on my page.

Does anyone of you experts have an idea what I need to change in order to have the preview look the same as the view in the block editor? Thank you very much in advance for your help!

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