This line is an H1

So is this one

Three H1s on one page. A crawler cannot tell which one is the actual topic.

An H1 is meant to be the single most important label on a page, the headline. When a template makes the logo, the headline, and a sidebar title all H1s, a crawler gets three claims about what the page is about and has to guess. The topic signal you meant to send gets split three ways.

And this is the third H1

The usual cause is a shared heading component with a fixed level, dropped into places that should have been H2 or H3. Pick the one real headline, keep it as the H1, and lower the rest. Something like a logo should not be a heading at all; a styled span or div is the right tag for that.