I have been booking parts of our trip to Italy for late September, early October. By mistake, I booked a train trip from Venice to Rome on the morning of October 1. Note to self: don't book non-refundable parts of the trip when distracted by the grandkids! I booked the Super Economy fare so can't cancel, change or get a refund. If anyone on the forum can use these two tickets, please let me know. We can email them to you or give them to you in person in Venice. It is the Frecciarossa train leaving at 9:25 a.m. from Venice SL and arriving in Rome Termini at 1:18 p.m. The total fare for the two tickets was 97.80 Euros. Would like to recoup some of that amount but would also be OK if we don't. Would just like someone to use them. I assume it is like the trains here in North America where if you have a ticket, all they do is scan the barcode on the ticket.
If you are booking on the Trenitalia website, read the fine print about the MANY different levels of tickets and what you can and can't do after purchase.