Hi Luethoata89
Thank you for your request.
Tickets must bear the name of the person who is travelling. A modification is not possible, new tickets must be purchased and a refund requested. The passenger identity is checked on the train. I recommend that you contact the relevant sales department directly.
If you purchased these tickets from SBB:
For Swiss tickets, please use the refund request form.
For international tickets, call us on 0848 44 66 88 (CHF 0.08/min) or If you are calling from abroad, use the number +41 51 225 78 56
I wish you a nice evening.
Kind regards
NicolasK