Having trouble with Pre_Get_Posts

My question is pretty straight forward but I am really hung up on this one. I have read the Codex for Pre_Get_Posts and I believe I am doing this correctly but it’s just not working.

I have a custom post type in the theme I am using called Portfolio. The categories it uses are called project-categories. I am trying to make it to where anyone logged in cannot see a specific category. Here is my code so far

function exclude_category( $query ) {
if ( is_user_logged_in() && $query->is_main_query() ) {
$taxquery = array(
'post-type'=> 'portfolio',
'taxonomy' => 'project-type',
'field' => 'id',
'terms' => array( 94 ),
'operator' => 'NOT IN'
);

$query->set( 'tax_query', $taxquery);
}
}
add_action( 'pre_get_posts', 'exclude_category' );

Any help on this would be greatly appreciated.