Saving payment method in Stripe for one time pay pricing plan

I have integrated Stripe with Wix as a payment provider. In my Pricing Plans i have one plan for one-time payment.

What i want to achieve is after user submits the checkout form, his payment method is saved for created customer in stripe (now Wix creates only customer with a single registered payment).

I have read about saving card on file option for checkout, but the checkbox for that does not appear in checkout.

I know that for reccuring plan in Wix payment method is saved for the customer in Stripe and i want to achieve the same thing for one-time payment plan.