getting redirected to /blog after changing permalinks

When I try to access the blog on myurl.com or myurl.com/index.php I get redirected to myurl.com/blog/ and get a 404 error cause there’s no such thing on my server. This happened when I changed the permalinks to the pretty ones. If I remove wordpress’s code from htaccess, it works, but then of course permalinks are “ugly” again. How do I sort this out? Thanks.