Originally Posted by
Often1
As to the notice issue, it's clear from OP's repeated posts that he was issued BP's for an existing flight at an existing time. He did not show up for that flight as scheduled. He has admitted his mistake in this regard.
But it also seems clear that this was (a) not the flight OP booked, nor (b) the replacement flight that BA MMB showed him as booked on.
BA, as the ticket issuer, has to take responsibility for this miscommunication / system failure.