Hello Dayse
I don’t think that it is possible to amend the name, however you could obtain a refund of the card and buy a new one with the right name. Ask KKday again.
You could also call the SBB Contact Center with this number, but you would have to pay a handling fee of 10 CHF:
+41 51 225 78 56 (24/7, waiting times may occur).
Kind regards
Danhiel