JS Support Ticket – Auto create WP account

wp_create_user is your friend!

It takes a username, password, and email:

wp_create_user( $username, $password, $email );

And here’s an example:

$user_id = username_exists( $user_name );
if ( !$user_id and email_exists($user_email) == false ) {
    $random_password = wp_generate_password( $length=12, $include_standard_special_chars=false );
    $user_id = wp_create_user( $user_name, $random_password, $user_email );
} else {
    $random_password = __('User already exists.  Password inherited.');
}

Since your ticketing system is not a part of WordPress core, and no details are provided, you’ll need to provide somewhere that will run code when a new ticket is created, be it a webhook or an action depending on how tickets are implemented.

You can find more information, including examples here