problem in Map-catagories-to-page

i am using map-catagories-to-page plugin to assign categories to my pages now the issue is i am not able to get my pages on base of category how should i do this

https://localhost/wordpress/?page_id=401

i am able to see my page on this url but fails in

https://localhost/wordpress/?cat=50 shows nothing (here i want to display all my pages in the category 51 how can i ?