My website is available for some users, but for some it is not

I've built a website (https://atpmetamorfoza.pl/) that loads properly for some users, but for some it just won't (around 10%). They see something like this: https://ibb.co/TtRjr1v.
translation to English:
Page title - "website unavailable"
Button - "go back"
Title with link below - "visit the website".

Neither of these buttons work. This page is built with wordpress + elementor + some custom css. Do you know where should I look for solution?