In order to fix this you must change the item back to what it was when the listing ended.
Most of the time this will be stock that the customer changed.
--if the stock now says 25 and you are getting this error, you must change the stock back to 0 and hit UPDATE ITEM.
--At this point you can add back in the 25 and now do a RETRY CHANNEL RELIST
--If you get another error fix as normal and then try another RETRY CHANNEL RELIST and that will list the item as intended.