“Warning: Invalid argument….”

Suddenly getting this error on some pages of client’s site:
Warning: Invalid argument supplied for foreach() in /home/65/91/2909165/web/wp-content/themes/make/inc/builder/setup.php on line 95

Here is the code in that area:

public function read_layout( $sections, $post_id ) {
		$layout = get_post_meta( $post_id, '_ttfmake_layout', true );

		if ( ! empty( $layout ) ) {
			$layout = maybe_unserialize( $layout );
			$sections = array();

			foreach ( $layout as $section_id ) {
				$section = get_post_meta( $post_id, "_ttfmake_section_{$section_id}", true );
				$section = maybe_unserialize( $section );
				$sections[] = $section;
			}
		}

		return $sections;
	}

This is what is on line 95:
foreach ( $layout as $section_id ) {

Thanks in advance

The page I need help with: [log in to see the link]