Since last night the prices have been incorrect when you search for items on the Trading Post. Once you click on the item the price is shown correctly; it’s only wrong in the search page. The prices there seem to be fixed to what they were at some point last night.
Possibly related: The prices also aren’t updating in the browser version of the TP (http://tradingpost-live.ncplatform.net/authenticate?account_name=Guild Wars 2) – they show the same prices as last night. GW2 Spidy (http://www.gw2spidy.com/item/19697) uses that website to update and the prices seem to have been broken since around midnight last night (patch time, perhaps?).
Hopefully this can help you fix the problem!