How to validate a Text field?

Hello,

I have added an “Email” and a “Confirm Email” field as both of type ‘Text’.

Under the “Billing” tab, I can the Abbreviation of these two fields, as: “email” and “myfield2”.

I have written the following php code with my themes’s functions.php file, to check whether the entered email and confirm email do match, but it is Not at all working:-
————————————————————————————

add_action('woocommerce_checkout_process', 'is_email_match');

function is_email_match() { 
    $email1 = $_POST['email'];
    $email2 = $_POST['myfield2'];
    // your function's body above, and if error, call this wc_add_notice
if ($email1<>$email2)
{
    wc_add_notice('Hey... Email and Confirm Email should match','error');
}
}

Please let me know where the custom field names can be found.

Thanks.