Cant import demo

Hi,

So I installed the theme and tried to instal the demo, but it gave me an error it said:
To protect your content the demo importer only works when WordPress is fresh installed. Please re-install WordPress with the default settings if you want to import the demo data.

I just freshly installed WordPress and after that, I imported this theme from my backup since the download on the website is down.

I don’t have a clue what to do actually