Find A Friend From 360 What Does " At This Time You Cannot Add This Person As A Friend? On 360 From My Favorites?

What does " at this time you cannot add this person as a friend? on 360 from my favorites? - find a friend from 360

On my list of favorites in 360, when I invite someone to try to be my friend, told me that at this moment I can not invite this person as a friend? How can I invite to make friends?