Why can't I receive chat notifications from this one person on Facebook?

[Rosie]

I haven't been recieving her chat messages at all and I have to check on my own if she has ever messaged me. I already compared the settings below the Friends thingy on her page to someone I do get notifications from and fixed it but it still doesn't work. What am I missing??
Thanks Helo, but my volume is perfect and I receive notifications for chat from everyone else except her. I checked all the settings imaginable but nope. thanks anyways.

[Helo I Is Artaayy]

I think it's a bug. It happens to me sometimes too, lately especially.
Maybe check your computer volume or your facebook notifications settings. I make goofs like that sometimes.

[Arturo A]

This is happening to me too, the same just with one contact. Annoying at best, haven't figured it out yet.