while administering a new user’s blog,”oopps, your link seems to be broken”error

helloo, I installed WMPU on my sub directory like: https://www.terakki.net/blogs
now when I create a new user, I get a message like: Your new Terakki Foundation Schools blog has been successfully set up at:
https://deneme.terakki.net/blogs/
But when I click the link to administrate my blog, always this message come: “oopps, your links appears to be broken”
So, what is the wrong point? This is about having subdirectory instead of subdomain? What should I do? I would be very happy to get help..