The ticket must bear the names of the passenger travelling. During the ticket check, the passenger has to present an official ID or passport for identification.
If the name on ticket does not correspond with the passenger travelling, the passenger will have to pay a surcharge of at least CHF 90 plus, in addition, the effective ticket cost.
It is not possible to amend names on the ticket after its purchase.
Ps. We do have an English-speaking SBB Community where you can find useful information on how to use tickets: