question

I followed this guide. https://clover.github.io/hosted-checkout-codelab/walkthrough/adding-the-checkout-component/

Made sure everything is right but I'm getting the following response every time

I am using the correct API tokens according to the docs.

Here is the code I'm trying to get working

  async startCheckoutSession() {
    let authKey = 'Bearer ' + 'replace with Private Token';
    let mId = 'replace with Merchant Id';

    try {
      const checkoutSession = await fetch('https://sandbox.dev.clover.com/invoicingcheckoutservice/v1/checkouts', {
        method: 'POST',
        headers: {
          Authorization: authKey,
          'X-Clover-Merchant-ID': mId
        },
        body: JSON.stringify({
          "customer": {
            "email": "email@example.com",
            "firstName": "Example",
            "lastName": "Customer",
            "phoneNumber": "223-555-0002"
          },
          "shoppingCart": {
            "lineItems": [
              {
                "name": "Apple",
                "unitQty": 1,
                "price": 100
              },
              {
                "name": "Orange",
                "unitQty": 2,
                "price": 75
              }
            ]
          },
        })
      });

      const res = await checkoutSession.json();

      if (!checkoutSession.ok) {
        throw res;
      }

      window.location = res.href;

    }
    catch (e: any) {
      console.error(e);
    }
  }

Please help if you have an idea.

Do I need my developer account verified in order to make requests?