PHP error function 'lh_remove_categories'

Hi,
I want to display the category meta above the title of an article (both home and single page), so I used that code in function.php child theme:

add_filter( 'generate_category_list_output','lh_remove_categories' );
function lh_remove_categories( $categories ) {
	if ( is_single() ) {
		return '';
	}
  if ( is_home() ) {
		return '';
	}
	
	return $categories;
}

add_action( 'generate_before_entry_title','lh_single_cats_above_title' );
function lh_single_cats_above_title() {
	if ( is_single() ) {
		$categories_list = get_the_category_list( _x( ', ', 'Used between list items, there is a space after the comma.', 'generatepress' ) );
		if ( $categories_list ) {
			printf( '<span class="entry-meta cat-links"><span class="screen-reader-text">%1$s </span>%2$s</span>',
				_x( 'Categories', 'Used before category names.', 'generatepress' ),
				$categories_list
			);
		}
	}
  if ( is_home() ) {
		$categories_list = get_the_category_list( _x( ', ', 'Used between list items, there is a space after the comma.', 'generatepress' ) );
		if ( $categories_list ) {
			printf( '<span class="entry-meta cat-links"><span class="screen-reader-text">%1$s </span>%2$s</span>',
				_x( 'Categories', 'Used before category names.', 'generatepress' ),
				$categories_list
			);
		}
	}
}

The problem is this error in my error_log.php:
PHP Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'lh_remove_categories' not found or invalid function name in /home/****/public_html/wp-includes/class-wp-hook.php on line 286

How can I fix it?

Thanks