passing profiles to the https://a.klaviyo.com/api/v2/list/{list_id}/members endpoint

Hello

I need help sending data to https://a.klaviyo.com/api/v2/list/{list_id}/members using javascript.
getting error msg as  “Error sending event:”
 Please see my code below: 
 

 const apiKey = 'my api ';
   
    const url = `https://a.klaviyo.com/api/v2/list/{list_id}/members`;

    // The data to be sent as the request body
    const data = {
        api_key: apiKey,
        profiles: [
            {
                email: 'test@example.com',
                $first_name: 'Test',
                $last_name: 'Test',
                $phone_number: '206-234-2345',
                $response: "1"
            }
        ]
    };

    // Options for the fetch() function
    const options = {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json'
        },
        body: JSON.stringify(data)
    };

    // Send the request using fetch()
    fetch(url, options)
        .then(response => {
            alert("response.json() =" + response.json());
            if (response.ok) {
                alert('Event sent successfully!');
            } else {
                alert('Failed to send event:', response.statusText);
            }
        })
        .then(data => console.log(data))
        .catch(error => console.error(error.message));