Next.js with Drupal, X-Frame-Options: SAMEORIGIN, "Unsupported Media Type" while post using axios

Question

I am working on Drupal with Next JS in the same origin. I am posting data from Next.js to the Drupal site using the following function and data. I got an "unsupported media type" error.

As per the Drupal documentation JSONAPI post, I have defined the header "Content-Type": 'application/vnd.api+json'. I could not find out what is the issue. can anyone help me, please?

/** SUBMIT SHOPPING CART DATA */
export const submitShoppingCart = async (formData) => {

  console.log("Form Data", formData);


    /** FIRST GET SESSION TOKEN */
    const getSessionToken = async () => {

      try{
        const response = await axios.get(baseurl.url + 'session/token');
        if(response.status === 200){
          const data = response.data;
          console.log("token data: ", data);
          return data;
        }else{
          console.log("token error: ", response);    
        }
        
      }catch(error){
        console.error("Error: ",error);
      }

    }

    const token = getSessionToken();

      const config = {
        headers: {
          "Content-Type": 'application/vnd.api+json',
          "X-CSRF-Token": token
        }
      };


  /**
   * (2) Submit Shopping Cart Data
   */
      const url = `${baseurl.url}jsonapi/node/sales_book`;
      try {
        const response = await axios.post(url, config, formData);
        if (response.statusCode === 200) {
          const data = response.data;
          console.log("POST Success . :", data);
        } else {
          throw new Error(`Error submitting shopping cart data: ${response.statusText}`);
        }
      } catch (error) {
        console.log("Error submitting shopping cart", error);
      }


}

Post Data

setFormData({
        "data": {
              "type": "node--sales_book",
              "attributes":
              {
                "title": "Shopping Cart",
                // "field_client_country": userCountry,
                // "field_client_email": userEmail,
                // "field_client_grand_total": grandTotal,
                // "field_client_id": uid,
                "field_client_name": username,
                // "field_client_phone": userTel,
                // "field_client_time_zone": userTimeZone,
                // "field_items": cartItems,
              },
            }
        })

I got the following errors:
"detail: "No route found that matches "Content-Type: application/json" "status": 415 title: "Unsupported Media Type".