Did you not set a valid publishable key Stripe?

Question

Stripes

Piece of code:

<form action="/code" method="POST">
    {{ csrf_field() }}
 <script
    src="https://checkout.stripe.com/checkout.js" class="stripe-button"
    data-key="here_goes_my_test_publishable_key"
    data-amount="999"
    data-name="Demo Site"
    data-description="Widget"
    data-image="https://stripe.com/img/documentation/checkout/marketplace.png"
    data-locale="auto">
  </script>
</form>

//вернет ошибку
You did not set a valid publishable key. Call Stripe.setPublishableKey() with your publishable key. 
For more info, see https://stripe.com/docs/stripe.js

Answer 1

data-key="here_goes_my_test_publishable_key"
This is where your "publishable key" or "published key" is needed. Find them in Account=>Api Keys in Stripe.