[Sciolist]

NETeller keep going down without neccessarily telling PokerStars, is how this ends up happening. Alternatively, they go down, a lobby message is posted, but the person cashing out doesn't notice.

The transactions won't go missing though, they'll return eventually. If you don't get a response from support in, say, 90 minutes, the chances are that the mail never arrived. Alternatively, it's possible there's been an email meltdown and the queue is several hundred long, but that's pretty rare...