Hello AfonsoLimao
Welcome to the SBB Community.
This is not the official SBB responding.
We are a customer support page run by volunteering travel experts. Thus, we are neither selling nor refunding anything 🙂
If you purchase the Swiss Travel Pass from SBB with an user account, you can cacel the STP for free until the day before its validity start date. The CHF 10 is requested when you purchase it as a guest.
But why to purchase the STP now if you unsure yet whether you will be able to make the trip? Purchasing it from SBB, you can also do so on the day of arrival, either online or at the ticket desk, at the same cost as now. Great, right?
Kind regards,
Roland