h4 after h1

Hi, I didn’t get any answer since more than 2 months and I still have the issue, that there is a h4 after an h1 like here:
https://de.wordpress.org/themes/inspiro/preview/?pattern_name=inspiro%2Fblog-posts

How can I avoid that because of accessibility and SEO?

Thanks, @brisch

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