Pagination issues

I’m getting crazy with WordPress pagination.

Using archive, category, author page when I load the url with page parameter the I get a 404 error.

https://localhost/test-blog/?cat=3 works perfect
https://localhost/test-blog/?cat=3&paged=2 get me 404 error and so on with 3, 4, 5.

Im using this pagination: https://www.kriesi.at/archives/how-to-build-a-wordpress-post-pagination-without-plugin