Error Message Container

<primer-checkout client-token="your-token">
  <primer-main slot="main">
    <div slot="payments">
      <primer-card-form></primer-card-form>
      <primer-error-message-container></primer-error-message-container>
    </div>
  </primer-main>
</primer-checkout>

<primer-checkout client-token="your-token">
  <div slot="main">
    <primer-payment-method type="PAYMENT_CARD"></primer-payment-method>
    <primer-error-message-container></primer-error-message-container>
  </div>
</primer-checkout>

checkout.addEventListener('primer:state-change', (event) => {
  const { paymentFailure } = event.detail;
  if (paymentFailure) {
    document.getElementById('my-error').textContent = paymentFailure.message;
  }
});