Dear @arminunruh ,
thanks for your message.
First, i changed the text formats from p to H1 etc. and then, I changed this again on each site in the gridder to be sure, that these text-format changes have been also affected there.
The double/duplicate content is not visible on the site itself but in the source code. That leads to the »duplicate H1, H2 content« error message in the SEO-Tool’s check (because it thinks, this content is »visible« twice).
The site is www.matteroffact.de – if you take a look at the source code, you’ll find the H1 example twice:
<h1 class="_verybig">Wir pressen <br />dein Vinyl!</h1>
... in line 1891 and then again in line 1941
Or on this site as well the H2: https://matteroffact.de/vinyl_produktion
<h2 class="_verybig">Wir produzieren deine Vision!</h2>
... first in source code line 1910 and second in line 1974
Or the H3:
<h3 class="_Zwischenhead">Vinyl in höchster Qualität!</h3>
twice in line 1903 and line 1967.
Thanks again for your help!
Greetings from Cologne
Alex