sidebar for custom post type

Hi, I just created child theme with a custom post type with the template files single-centri.php and content-single-centri.php I want to display a sidebar in this post type so I added in the template file the get_sidebar() line, but when I create a new centri post the sidebar don't work and I just see the word "Array" under the content just before the footer instead that on the right or left side of the post. You can see what I'm talking about in this URL: http://www.waterphysiotherapy.com/es/centro-rehabilitacion/aaa/ How can I fix this problem? Thanks