I am trying to upgrade to a higher plan from the existing free plan. I added my billing information successfully and trying to pay.
When I paid the bill, I received an email to confirm my payment. When I clicked the Confirm Payment button in the email, I get the following error, thus preventing me from upgrading.
Update: I got an additional message on the Klaviyo billing page as follows:
This payment requires additional user action before it can be completed successfully. Payment can be completed using the PaymentIntent associated with the invoice. For more details see: https://stripe.com/docs/billing/subscriptions/overview#requires-action
However, this page describes updates to the payment at the back end, which is not in my control.