Define variable with IF ELSE statement - Wordpress

I'm trying to define and output a $store_icon variable based on the IF ELSE condition.

I'd like to show a store icon if the store icon image exists, if it doesn't, then I'd like to show just a regular profile avatar (using an existing shortcode)

This is as far as I can get:

$store_icon_src = wp_get_attachment_image_src( get_user_meta( $vendor_id, '_wcv_store_icon_id', true ), array( 40, 40  ) ); 
$store_icon     = '';

if ( is_array( $store_icon_src ) && !empty($store_icon_src) ) {
     $store_icon = '<img src="'. $store_icon_src[0].'" alt="Store Name" class="store-icon" width="40" height="40" />';
} else {
     $store_icon = do_shortcode( '[profile-avatar]' );
}

echo '<div class="store-icon">'. $store_icon .'</div>'; 

  

It kinda works, but I need both options to be output inside the echo html div tags.

Currently they're not, the first option seems to be called outside the echo.

What am I doing wrong here?