Kraken, your trading engine is next to useless. 
I submit a market order.  Kraken says it "may have" failed.  The oders page shows no orders pending.
So I submit the order again, it "fails" again.  I submit a third time, and it executes.
But in the meantime, the first order, the one that supposedly failed, and which DID NOT SHOW UP ON THE ORDERS PAGE,
HAS NOW EXECUTED too!
If you're going to tell me that an order failed, or "may have" failed, and it does not show up on the pending orders page, then CANCEL THE
FUCKING order.