I have not had that particular problem. I was going to advise you to take a look at your Watchlist task bar, and check the second box. If it is set to "Active" instead of "ended" or "All", you will not see any items you were watching for auctions that may have ended.
I looked at my past Gunbroker Support requests, and saw that there was a time I could not access my Watchlist at all. Logging out and then logging back in fixed it. And after their last so-called upgrade, I can no longer use "New Since Last Visit" as my default search function. Most items that I already saw on my previous visit still come up. The other problem I have with the last so-called upgrade is that the Search criteria got much broader. For example, if I search for "Double Rifle", I now get nearly 4500 results, and the vast majority have absolutely nothing to do with Double Rifles. It used to work much better, but apparently they think that people will sift through 186 pages of crap to find a couple dozen double rifles.