20/08/16, return Favignana - Trapani of the late 2...

20/08/16, return Favignana - Trapani of the late 21 which has gradually accumulated up to 1 hour without any warning from the staff.
Called (I, replacing the ticket office that should have done so) the venue, they don't know what time it arrives!
Meanwhile, given that the other 21.15 and 21.35 ferries have regularly sailed, the ticket office proposes (astutely) to embark on one of these for an additional cost of 2.20 euros each.
I'm sorry, I'm not used to paying for the delays of others.
I will demand reimbursement of the ticket.