I'm trying to increase the amount of backlinks for a website I have and to do that I have been creating other websites and putting backlinks in them to my original website. Unfortunately when I go on ahrefs to check whether any new backlinks have been found there is none (This is several days after I have created the site too not just straight away), I have added sitemaps to these sites and they have been crawled when I've done this in google search console and Bing webmaster tools so I know the pages have been crawled, the links are not behind a login page or anything like that so they shouldn't be getting blocked or anything.
I don't just have the links by themselves on the page there is other content there as well, not sure if that would be an issue but if it is it can't be that, and I am not sure why they aren't adding to my websites SEO?