Downloading HTML files of a website with wget just give me a index.html

I am trying to download 1000 HTML pages from a specific site (https://isna.ir/) with wget in a recursive way (it is part of our course assignment) but it just downloads an index.html file. I tried a lot of options that wget provides, but none of them work, also I tried --reject="index.html" The command: wget --recursive -nd -np --random-wait -U Googlebot -P ./isna_crawl https://isna.ir/