Custom Post and Prev/Next Post Link

Hello,

On my theme twentytwelve, I create a custom post type
I do not succeed to display the post and prev post link on my custom post type. On my single-custom-post.php file I have this to display the post link :

<nav class="nav-single">
					<h3 class="assistive-text"><?php _e( 'Post navigation', 'twentytwelve' ); ?></h3>
					<span class="nav-previous"><?php previous_post_link( '%link', '<span class="meta-nav">' . _x( '&larr;', 'Previous post link', 'twentytwelve') . '</span> %title' ); ?></span>
					<span class="nav-next"><?php next_post_link( '%link', '%title <span class="meta-nav">' . _x( '&rarr;', 'Next post link', 'twentytwelve' ) . '</span>' ); ?></span>
				</nav><!-- .nav-single -->

How can I make it work displaying my last post even if is not a custom post ?

Thank you for your help

https://ww.wp.xz.cn/plugins/types/