Guild Wars 2

hi i was just wondering, is this a bug?
i try to sell things on the TP, sometimes it will let me sell maybe 5 items, then it say error attempting to sell, sometime it doesnt let me sell anything.
ive tried character switching, and restarting the game client.
is there some sort of ports i need to forward or something?
whats going on here?

weird i lost nothing, i was doing map completion in rata sun when it went down….still 100%