Checkout has not been enabled

{
  "error": {
    "type": "request_error",
    "code": "transaction_checkout_not_enabled",
    "detail": "Checkout has not yet been enabled for this account, you may need to check with Paddle Support that the Paddle onboarding process has completed.",
    "documentation_url": "https://developer.paddle.com/errors/transactions/transaction_checkout_not_enabled"
  },
  "meta": {
    "request_id": "00000000-0000-0000-0000-000000000000"
  }
}