You need I believe to look at both yours and their profile page.
Check that both you and they have each other as friends, just because you have someone as a friend does not mean they have you as a friend.
If both of you are shown as each others friends then you need to click on the button to the right of this post that says FAQ Home. When you get that page in the first sentence you will find the words help request, click on that and explain what is happening.
I have never waited longer than one day for an answer, that has sorted everything out.
Home this works
Regards Alan