please ticket changes or cancellstion

Dear SBB. ch.

Hello,

I have a question about ticket changes or cancellation.

I purchased 2 tickets, from Grindelwald to Spiez (06:49, 11. Nov. 2018.)

(1. Ticket-ID: 120677893161 / Reference nr: 46555106 / Order no: 437624166)

(2. Ticket-ID: 936550090697 / Reference nr: 46555105 / Order no: 437624166)

But I want to change my schedule.

I hope to make a reservation(2 tickets), Grindelwald to Domodossla (06:49, 10. Nov. 2018.) - Not 11. Nov.

Would you please cancel my tickets? or changes my tickets?

Please, tell me how to do it.

Thank you for your help.

Many thanks,

Thank you for your question.

Unfortunately, I cannot cancel these tickets. Please contact directly our Railservice (+41 848 44 66 88).
My colleagues will be able to help you.

Thank you for your understanding.

Best Regards
NicolasK