Hello theringman2
You need an Arcobaleno Transfrontaliera ticket from Chiasso to Como. The cost is CHF 1.50, one way.
The GA Travel Card validity map shows that the GA Travel Card is valid as far as Chiasso, but not beyond this point. I don’t know how you came to the conclusion that the GA was valid.
GA Travelcard area of validity | SBB
Kind regards,
Roland
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