Not able to connect a subtemplate to a custom css style sheet

Howdy all. did put this up in the wordpress.org site. But the only suggestion that came up did not work.
Hope someone here can offer some good advice.
This is what I have in my functions.php

//load subtemplate aboutus
function aboutus_style() {
	if( is_page_template('aboutusSub.php') ) :
	wp_register_style('my-style', get_stylesheet_directory_uri() . '/css/aboutus.css', array(), '', 'all' );
	wp_enqueue_style( 'my-style' );
	endif;
}
add_action('wp_enqueue_scripts', 'aboutus_style');

that code above is recognized and the subtemplate picks up the css.
the code below. should work. but the page, w/the correct subtemplate added and selected as well in the admin create pages panel doesn’t.

//load subtemplate level3and4
function l3_style() {
	if( is_page_template('l3sub.php') ) :
	wp_register_style('my-style', get_stylesheet_directory_uri() . '/css/l3.css', array(), '', 'all' );
	wp_enqueue_style( 'my-style' );
	endif;
}
add_action('wp_enqueue_scripts', 'l3_style');

so for example the page http://thebigmeow.us/invest/reports/
or http://thebigmeow.us/engineering/oil-gas-and-chemicals/
are not picking up any styling.
is not picking up the styling assigned.
How can I fix this please?
thank you.
d

Hi pdxSherpa,

It could be the handle (the first parameter in wp_register_style) you’ve registered the second style with. You’re using my-style for both aboutus.css and l3.css. I think that the handle uniquely identifies the style so you’ll probably need different values.

See: http://codex.wordpress.org/Function_Reference/wp_register_style