I m calling an External HTTP API into WordPress and I am getting responses but my problem is i want to print Current logged in user email inside the url dynamically. I am able to print or display Current logged in user email in wordpress site with the following code:

$current_user = wp_get_current_user();
$custemail=$current_user->user_email; 
<?php echo $current_user->user_email;?>

But I wan to print this in the API URL

https://httpapi.com/api/customers/details.json?auth-userid=XXX&api-key=XXX&username=<?php echo $current_user->user_email;?>

username=<?php echo $current_user->user_email;?>

So I will get the API response based on the current user logged in email address as a selector. But not getting any response using the echo code in the url. I cant figure out whats wrong?