edu-clean theme related question

hi there.
I have a guy, who claimed around 7 blogs, straight after signup. I told him to take thigns slowly and don't claim blogs he won't use, so he went ahead and deleted some of them he did not plan to use....

anyway, one of those blgos was his main blog, the one he signed up first it seems.

now when he is logged in and visits the main page which is using the edu-clean theme, the links to my dashboard and write a post don't work anymore for him meaning they still link to his "original" blog, the one he deleted meanwhile. They do work for any other logged in user and point to their respective blogs.

Any ideas what could have gone wrong here?