wget downloads only the loading page of the website

I want to download a password protected website, because this site is not accessable in the future. I managed to download something, but when I opened the index file, it shows only the loading page of the site and I cant get furter. So my question is: how can I pass the loadig page? Device: laptop with Windows 10.

This is what I have so far: wget -p -nH -H -k -E --random-wait -r -p -e robots=off -U --user=**** --password=**** https://example.com