Hello Teessoowiec19
You cannot purchase a Swiss Pass yet simply order the card as the Swiss Pass card is handed out free of charge.
What you have to purchase, though, is the subscription that is loaded onto the card.
Simply go to the GA Travel Card product page and start the purchase process from there. Log in with your SwissPass account when being asked to do so. The product will then be added to your customer account and displayed in the SBB Mobile app provided your card is successfully linked with your account.
If all sounds too overwhelming, please go and see an agent at one of the travel centers. There, they can also provide you with a temporary SwissPass paper document for instant travel.
Kind regards,
Roland