Required and Optional Fields

These fields are required for creating a subscription with an existing plan:
subscriptionInformation.planId
Required when you are using a standard plan.

Optional Fields

subscriptionInformation.originalTransactionId
Required to create any credit or debit card subscription.
Including this field ensures better authorization rates and Strong Customer Authentication (SCA) compliance where necessary.
subscriptionInformation.originalTransactionAuthorizedAmount
Additional required field for a Diners or Discover card.