Hello KIMMINSUN
What would you like to change? A transfer to another person or rectifing the travellers’s name due to a typo or missing mitddle name?
A complete name change (new person) is not possible. Saver offers are not subject to refund unless you bought two identical tickets for one and the same person.
More information in the refund policy you can find here:
https://www.sbb.ch/en/help-and-contact/refunds-compensation/refunds-compensation/ticket-refunds.html
Kindly see our English speaking community:
https://community.sbb.ch/t5/Questions-and-answers/ct-p/forum_en
Best regards,
Roland