Request tab at my profil/account page

Hi,
I have a big problem with thanking the translators who did answered on my requests, because under the list "xx opened requests by ..." I don't have anymore the list of "xx completed requests for ...". A few days ago the list was (after a long time, maybe one or two months) there for a day, I think. Now it's gone again. Can someone please check out the problem? Thank you... and sorry for not so well english speaking;)