XMLHttpRequest() POST returns 405 error; method not allowed

My html code:

    <h2>Please finalize your details</h2>
    <form id="details" method="post" class="form">

        Full name: <strong name="name_1">ABCDEF</strong><br><br>
        ID No:<strong name="org_number_1">123</strong><br><br>
        Mobile No:<strong name="ph_number_1"">1234567890</strong><br><br>
        
        E-mail: <strong name="email_1">ABC@DEF.COM</strong><br><br>
        ID Card: <img src="profile.png" alt="preview" name="image" style="width: 100px; height: 100px;"><br><br>

        <button id="go">It's correct</button>
        
    </form>

My javascript:

document.getElementById('go').addEventListener('click', submit);
function submit(){

    var nme=document.getElementsByName("name_1")[0].innerHTML;
    var id=document.getElementsByName("org_number_1")[0].innerHTML;
    var phone=document.getElementsByName("ph_number_1")[0].innerHTML;
    var email=document.getElementsByName("email_1")[0].innerHTML;
    var img=document.getElementsByName("image")[0].src;

    const xhr=new XMLHttpRequest();

    xhr.onload=function(){

        const serverResponse=document.getElementById("response");
        serverResponse.innerHTML=this.responseText;
    };

    xhr.open("POST", "database_registration.php");
    xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    xhr.send("name="+nme+"&id="+id+"&phone="+phone+"&email="+email+"&img="+img); //this line throws the error "Failed to load resource: the server responded with a status of 405 (Method Not Allowed)"
}

I am executing my code in Visual Studio Code editor and my project location is in:

C:\Users\Abhishek\Desktop\Web-dev stuff\XAMPP\htdocs\Stack hack 20 20

This is the error:

Not only that, I've also tried working with Fetch API, but it throws the same error too. What do I do now? How can I make it work?

from XMLHttpRequest() POST returns 405 error; method not allowed