Why does the WordPress paginator return a 404 error?

Question

WordPress

Good afternoon, I ran into the following problem: there is a site on wordpress, there is a blog section (mysite.com/blog). Posts are displayed on this page, but the post type is custom (for the blog, it was necessary to create a separate post type - blog_post). Links to custom posts look like this - /blog/blog_post_1. But at the same time, pagination does not work (the link of the paginator to the next page - /blog/page/2, etc.) - error 404. The
question is - how can I fix pagination without going too deep into picking the vp code?