Clay for the Clay Man

[The Puzzler]

This quest seems a bit buggy.  If you take it while someone else has it, when they close it, it closes for you as well.  You get the ping and everything.  From the point that the other person closes it you can no longer gather more clay, and when you turn the quest in it tells you that you have already taken the quest, and then flags you for cheating.  Screenshots available.