You do not need a 1 credit package / bundle / pass in order for a customer to book and pay for a single class.
To accept pay-as-you-go (PAYG) bookings on your sessions, you would simply select Credit or debit card via Stripe as a Payment option on your sessions making sure to enter the PAYG price within the Price field on the session creation page.
This set up allows a customer to book and pay directly on the session itself which means they're not having this added step of purchasing a 1 class package / bundle / pass first.
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