Thank you! Looks like the problem was in the fact that i didn’t go step by step, instead i opened all in tabs first, the permalink, the hide my wp, the empty cache – so when i changed permalink structure and then i go other tab in my browser, hide my wp, and then after i applied medium settings, it automaticaliy returned permalink structure to default. So now, when i go step by step, i managed to configure this without a problem. Thank you for all the help, best reagards and best of luck in your future projects! 🙂