JCH
You have probably entered mm-dd-yyyy while in the rest of the world we use dd-mm-yyyy.
It should be okay for Switzerland, provided there is no half fare advantage resulting from the wrong date and your name on the ticket is exactly as in your passport. You must carry it (no copies, no photos) while using e-tickets on Swiss public transit serrvices.
For Italy, we cannot say.
Kind regards,
Roland