My Father's LIRR train had a mechanical issues which delayed his arrival into PENN causing him to miss his ACELA to BOS.

He went to CLUB Acela where the agent first tried to exchange his ticket, but that failed as it had already been lifted, which the agent said is happening a lot and she was unsure as to why.

She then had to call on the phone to some sort of support desk which "un-lifted" the ticket and then she was able to put him on a later departure.

All in all, if tickets can be lifted without being scanned, there is a flaw in the system.

Dan