This error means that additional authentication is required for the payment to be approved, and currently SyncWith doesn't support this unfortunately.

The full error message is:

Payment for this subscription requires additional user action before it can be completed successfully. Payment can be completed using the PaymentIntent associated with `subscription.latest_invoice`. Additional information is available here: https://stripe.com/docs/billing/subscriptions/overview#requires-action

We see this issue sometimes with users in India attempting to purchase a subscription with a credit card from India.

We recommend you try your purchase again with a different credit card.