no such sku when called redirectToCheckout

[nwaynway17]

I want integrate with Stripe Checkout Client in my asp.net application.
Before I integrate, I am testing sample check-out-onetime-payment project in GitHub.
I also already created stripe account.
I want to test with test mode Public Key and Secret Key first before I go live.
So, I tested sample check-out-onetime-payment project in GitHub using my test mode Public Key and Secret Key.
But, I got Integration Error : No such SKU when called redirectToCheckout.
Mean, cannot test with test mode Public Key and Secret Key?
Please give me any other suggestion.
Thanks a lot.

[thorsten-stripe]

Please only file issues here that you believe represent actual bugs or feature requests for this sample.

If you're having general trouble with your Stripe integration, please reach out to support using the form at https://support.stripe.com/ (preferred) or via email to support@stripe.com.

If you are reporting a bug, please include the server language you're using, as well as any other details that may be helpful in reproducing the problem.

[thorsten-stripe]

This is likely related to an incorrect sku ID. Do follow the set up steps here: https://github.com/stripe-samples/checkout-one-time-payments/blob/master/client-only/client/README.md#setup