My last 3-month emails have disappeared since 2 days now. Can't reach specific Customer Service department. I seem to always get to "Quick fix tool", but its reports look good. There is a BUG in the application: I did not apply any filter, only "Smart View"->Starred/Unread shows them, but window freezes when I try to open them from this view.
My confidence in Yahoo Mail just dropped, I don't feel safe using it until my problem gets solved and the engineers know the cause, so they can fix it for the future.
Thanks!