This is due to the hair cut rule which comes into effect at 20% debt levels I believe. Since Hives price is so low the debt from HBD is currently at around 25% or so. We are now unable to convert HBD into Hive as a precaution until there is either less HBD in circulation or Hives price recovers in order to keep debt levels in check. I think once we get back over 10 cents things should be back to normal again. You can still sell your HBD on the internal market, however.