Seems like no one is online. But the problem was at the prefix which was wp_english. I had changed it to new_english with Better WP Security and because the english wordpress is separately at /en/ folder it totally messed with the root prefix which is like my_. So the english site’s prefix is now my_english. I changed it at the wp-config -file and the site is now up and showing. Almost yey! But… I can’t get into wp-admin. It shows partly like upper admin menu, but when I click Dashboard it says ‘You do not have sufficient permissions to access this page.’
I found a blog about it https://beconfused.com/2007/how-to-solve-you-do-not-have-sufficient-permissions-to-access-this-page-in-wordpress/
But this gets out of my skills. So I’m not going to continue any further. Luckily this site is only my site, not my clients. I feel really scared to do anything with Better WP Security, if it can mess a site this badly. I know someone at the server host can help me to fix this, but think about all the lost time and headaches it can cause.