I mentioned this in another thread here (which I can't find), but it's
happened again...

Just back from a recent trip to London, I noticed the balance was £8
less than it should have been. Looked on a ticket machine which stated
I'd done the journey:
"Heron Quays DLR - Unfinished
Unstarted - Woolwich Arsenal"

Every single trip to London I have done something similar to this has
happened and on every occasion it has involved the DLR at Canary Wharf
or Heron Quays.