Hi there.
In the last days, there's too much demand from the market bot and it's constantly out of credits. We are calibrating the buy/sell ratios for this new demand (in english: changing the prices) and it will work as follows:
A. If market has just enough bits, it will buy only rare items
B. If market has accumulated a determined treshold, will trade all others.
C. If market is broke, will only sell.
Our objective is that situation A is happening most of the time while B and C in odd circunstaces. This won't be a problem we solve in an update, but with constant observation of the market flow, over a few months. We appreciate your patience